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A Frequency Based Theory of Catalysts
··\1uch of chemistry invol\es energy. In the right place. right time. and right amount. energ) dfr.es the,.-----
P reactions. separations and other functtons of the chemical uni\erse. In the \.\-rong place. \Hong time. or ""ron Q \ ~
.imount. energ) can ruin a batch. create um~anted b:, -products. or otheN ise interfere"" ith the desired outc me.
,;.
Thus. -:hemical research is intimate!:, imol\ed ""1th the control of the t)-pe. amount. Jnd timing of energ) :mrodw..:t10n into a s:,stem:· \1icro,,.,ave-Enhanced Che:nistr:,: Eds. H\1 Kingston & SJ Has\ltell.l 997.
08:
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Background
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Chemical reactions are driven by energy. The energy comes in many
different fonns - chemical, thermal. mechanical, acoustic, and electromag-
netic. Various features of each type of energy are thought to contribute in
different ways to the driving of chemical reactions. Irrespective of the type
of energy involved, chemical reactions are undeniably and inextricably
intertwined with the transfer and combination of energv. An understanding
~*
~
::i9f energy is, therefore, vital to an understanding of chemical reactions.
,,,
Chemical energy drives a reaction by catalyzing it. Catalysts are
J,;:!:hemicals that speed the rate of a reaction, but are neither used nor consumed
!:;:!n the reaction. Many reactions are said to be catalyzed. That is, the addition
;:;pf a small amount of a chemical substance (the catalyst) can greatly speed the
i::xate of the reaction. How did this definition evolve?
••
In 1770, only 15 elements were known. After Boyle's recognition that
,JJ:hemistry was properly the study of matter', catalytic action was noted for
/,,the first time. In 1835, Berzelius proposed a theory of "catalysis". He
:::;believed that since the catalyst was unchanged by the reaction, a catalytic
:'.J"force'' must be involved. By the tum of the century the kinetic theory of
chemistry had been developed. In 1911, Ostwald proposed the modem
theory of catalysis, which has stood unchallenged for nearly one hundred
years. This theory abandons Berzelius' catalytic force, and states there are
five essential steps in catalysis:
1. Diffusion of the reactant to the catalyst site;
2. Bond formation between reactant and catalyst;
3. Reaction of the catalyst-reactant complex;
4. Bond rupture at the catalytic site to produce product;
5. Diffusion of product a\vay from the catalyst.
Thus. catalysts are thought to speed reactions by bonding with chemicals.
CJtJ!) sis ,mJ ChemicJI processes: EJs. Pc..m.:e R & PJtterson \\.R. Wik; & Sons. ICJ8 l. Page -1-
Thennal energy is used to drive chemical reactions by applying heat and increasing the temperature. The addition of heat increases the kinetic (motion) energy of the chemical reactants. A reactant with more kinetic energy moves faster and farther, and is more likely to take part in a chemical reaction. Mechanical energy likewise, by stirring and moving the chemicals, increases their kinetic energy and thus their reactivity. The addition of mechanical energy often increases temperature, by increasing kinetic energy.
Acoustic energy is applied to chemical reactions as orderly mechanical waves. Because it is mechanical, acoustic energy increases kinetic energy of chemical reactants, and can also elevate temperature. Electromagnetic (EM) energy consists of waves of electric and magnetic fields. EM energy increases kinetic energy and heat in reaction systems. It also energizes electronic orbitals in some reactions.
Both acoustic and electromagnetic energy consist of waves. The number of waves in a period of time can be counted. Waves are often drawn,
;:~s in Figure 1.. below. Usually, time is placed on the horizontal X-axis. The
i:;·ertical Y-axis shows the strength or intensity of the wave. This is also ;'1~alled the amplitude. A weak wave will be of weak intensity and will have ::~ow amplitude (Figure 2.a., below.) A strong wave will have high amplitude
;;~~Figure 2.b.)
Amplitude j
Time -
Figure 1. - Wave representation (acoustic or electromagnetic)
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- .fJF,,__,,
t,J PJ 1L}1!11
i . ..\mplitude
i Amplitude
Time -+
( a)
Time -+
Figure 2. - Waves of different amplitudes but the same frequency. (a) Low intensity \vave with low amplitude. (b) High intensity wave with high amplitude.
Traditionally, the number of waves per second is counted, to give the ::frequency.
Frequency = Number of waves/ time = Waves/second= Hz.
Another name for "waves per second", is "hertz" (abbreviated as Hz) 1:so named for Heinrich Hertz who did much of the early research in-defining ;;~lectromagnetic waves. Frequency is drawn on wave diagrams by showing :Si~ifferent numbers of waves in a period of time (Figure 3. (a) below.) It is /]Hso drawn by placing frequency itself, rather than time, on the X-axis i::~Figure 3. (b).).
Amplitude T
• •
0.5
1
Time (seconds)
(a)
0
l
2 34
Frequency
(b)
Figure 3. Frequenc~ diagrams. (a) Time on the X-axis. 2 and 3 Hz frequency waves. (b) Frequcncv on the X-axis. 2 and 3 Hz \\a\es.
-
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Energy waves and frequency have some interesting properties, and
combine in interesting \vays. The manner in which wave energy transfers
and combines, depends largely on the frequency. Say, for instance, that we
combine nvo waves of energy, each of the same amplitude, but one at a
frequency of 400 Hz (waves per second) and the other at I00 Hz. The waves
will combine and add their frequencies, to produce a new frequency of 500
Hz. the sum frequency. They will also subtrac_t \vhen they combine, to
produce a difference frequency of 300 Hz. All wave energies add and
subtract this wav, and it is called heterodvning. The results of heterodvning
.,
.I
"-'
'-'
are probably familiar to most people as the harmonies in music.
There is a mathematical, as well as musical basis, to the harmonics
produced by heterodyning. Consider a continuous progression of
heterodyned frequencies. Using our example above, beginning with 400 Hz
and 100 Hz. we get 500 Hz and 300 Hz. If we heterodyne (add and subtract)
these new frequencies, we get 800 (500 + 300) and 200 (500 - 300).
1;[:iHeterodyning 800 and 200, gives us 1,000 and 600 (see Figure 4. below).
',""
Soon a mathematical pattern begins to emerge. Both the addition and
:,,;:the subtraction columns contain alternating series of numbers that double
::nwith each set of heterodynes. In the additive column, 400 Hz, 800 Hz, and
,"••; 1,600 Hz, alternates with 500 Hz, 1000 Hz, and 2000 Hz. The same sort of
:;·/doubling phenomenon occurs in the subtraction column.
FIGURE 4. - Heterodyne Progression
Initial Frequencies (Hz)
400
And
100
400 + 100 = 500
and
400 - 100 = 300
500 + 300 = 800
and
500 - 300 = 200
800 + 200 = 1000
and
800 - 200 = 600
1000 + 600 = 1600
and
1000 - 600 = 400
Sum <Added) Frequencies (Hz) 400 500 800 1000 1600 2000
3.200
Difference (Subtracted) Frequencies (Hz)
100
300
200
600
400
1200
800
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Heterodyning of frequencies is the natural process that occurs whenever wavefonn energies combine. It results in patterns of increasing numbers that are mathematically derived. The number patterns are multiples of the original frequencies. These multiples are called hannonics. For instance, 800 Hz and 1600 Hz are harmonics of 400 Hz. In musical terms, 800 Hz is one octave above 400 Hz, and 1600 Hz is two octaves hi.g... her. Most of us have an intuitive understanding.... of harmonics throug.....h our exposure to music. Few understand the mathematical heterodyne basis for harmonics, which occurs in all waveform energies, and thus in all of nature.
The mathematics of frequencies can take us to even more interesting places than the concert hall. Frequency heterodynes increase mathematically in visual patterns (see figure 5. below).
-3000 +---+--+---+--...,_---l--+--+---1------1-
N
~
(>'
~2000 +----------+--+---+--+--+---+-
:::, O" ~
I.L.1000 - - - - - - -
0
Heterodyne generation
Figure 5.• Visual pattern created by heterod)ned series from Figure 4.
Mathematics has a name for this - it is called a fractal. A fractal is defined as a mathematical function which produces a series of self-similar patterns or numbers. Fractal patterns have spurred a great deal of interest because they are found everywhere around us in nature. They can be found in the patterning of large expanses of coastline, all the way down to microorganisms. They are found in the behavior of organized insects and in the behavior of fluids. The visual patterns produced by fractals are very characteristic (see Figure 6.~)
:Enc: clopi;:dia of Ph: sics: Eds. Li;:mer RG & Trigg GL. \'CH Pub!. Inc.. 1991.
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A
heterodv-ne
is
a
mathematical
function.
governed
'-
bv "
mathematical
equations, just like a fractal. A heterodyne also produces self~similar patterns
of numbers, like a fractal. If graphed, a heterodyne series produces the same
familiar visual shape and fonn which is so characteristic of fractals. Com-
pare the heterodyne series in Figure 5. with the fractal series in Figure 6.
Figure 6. - Fractal diagram
Heterodynes are fractals - the conclusion is inescapable. Heterodynes id and fractals are both mathematical functions which produce a series of self-
similar patterns or numbers. All wave energies combine in heterodyne patterns. Thus, all wave energies actually combine in fractal patterns. Once you understand that the fundamental process of combining energies is itself a fractal process, it becomes easier to understand why so many creatures and systems in nature also exhibit fractal patterns. The fractal processes and patterns of nature are built in at a fundamentally basic level. As the scorpion said to the frog, "It's in my nature."3
Well, you say, nature is made up of more than just energy. There is quite a bit of matter out there also. What about matter? Good question. After all, if energy can transfer and combine by heterodyning, what about
:The scorpion asked the frog to give him a ride across a stream. He promised not to sting the frog. Just as the frog carried the scorpion to the other side of the stream. the scorpion stung
him ;.in~\\a:,. When the frog :.isked \\h:,. the scorpion replied...It's in m: nature:·
Page - 6 ~ / ,;J-#-f9" • tJ "-' fl/4 lr1
matter? Chemical reactions occur between atoms and molecules, not just
-- between little bits of enern:v. The answer is, matter interacts bv heterodvning
"'
,,
.......
also. All matter. whether large or small, has \vhat is called a natural
oscillatory frequency. The natural oscillatory frequency (NOF) of an object,
be it atom or elephant, is the frequency at which the object prefers to vibrate,
once set in motion. The ~OF of an object is related to many factors such as
size, dimensions. and composition. Basically, the smaller an object is. the
smaller the distance it has to cover when it wriggles back and forth. The
smaller the distance. the faster it can wriggle back and forth, and the higher
its NOF.
Consider a wire composed of metal atoms. The wire has a natural
oscillatory frequency. The individual metal atoms also have unique
oscillatory frequencies. The NOF of the atoms and the NOF of the wire
heterodyne by adding and subtracting, just the way energy heterodynes,
NOFatom + NOF-.1,m: = Added Frequencyatom-\\Ire,
and
NOFatom - NOF\\ire = Subtracted Frequencyatom-\\lre'
If you stimulate an atom on the wire with the Subtracted Frequencyatom-
\1.ire, ( this experiment was actually done using a laser to generate the
subtracted
frequency
4 )
it
will
heterodyne
(add)
with
the
N O F .,..ire
to
produce
NOFatom• the natural oscillatory frequency of the atom,
Subtracted Frequencyatom-.. ire + NOF\\ire= NOFatom·
Matter heterodynes with matter the same way that wave energy does.
This means that matter combines in fractal processes also. It now becomes
doubly easy to understand why so many creatures and systems in nature
exhibit fractal processes and patterns. Matter, as well as energy, combines by
the mathematical equations of heterodynes, to produce harmonics and fractal
patterns. That is why we see fractals everywhere we turn.
There is a third leg to this stool. We already know that energy
heterodvnes with energv. and matter heterodvnes with matter. Can matter
,.,
1,,_..,
.,
heterodyne with energy? The ans\ver is yes. Remember our metal wire and
atoms? The Subtracted Frequencyatom-1,1,ire in the experiment \Vas provided by a laser. using electromagnetic wave energy at a frequency equal to the
Subtracted Frequencyatom-1,1,ire· The matter in the wire via its' natural oscillatory frequency, heterodyned with the laser's wave energy frequency. to produce the frequency of an individual atom of matter. So, energy and matter do heterodyne with each other.
This of course leads to the interesting curiosity ofjust how matter and
energy interact. It helps in understanding chemical reactions, to understand
energy and matter interactions. When energy encounters matter, one of three
things generally happens. The energy either bounces off the matter (reflected
energy), passes through the matter (transmitted energy), or combines with the
matter (heterodyning). The crucial factor which detennines which of these
three things will happen is - you guessed it - the frequency of the energy
,,,,,compared to the frequency of the matter. If the frequencies do not match, the
::;,;energy will either be reflected, or will pass on through as transmitted energy. :;~If the frequencies match either exactly or as harmonics (heterodynes), then
;:~:the energy combines with the matter.
,....
Think of matter as a glass of water. When energy heterodynes and
!:~~combines with the matter, it is just like adding another spoonful of matching
:;"''water to the glass of water. It all mixes and combines together until you
1::1:cannot tell what was in the glass and what was from the spoon. Add a
spoonful of oil to the glass of water however, and things will be quite
different. The oil and water don't match, so they will not mix. The oil will
float to the top of the glass, like reflected energy. So when the frequencies
of matter and energy match, they will ·combine by heterodyning. When the
frequencies do not match, they will not combine, and the energy will either
be reflected or transmitted. There is another term often used for matching of frequencies. That
term is resonance. A lot is written about resonance, much of it erroneous. It
all boils down to one simp.le concept. Resonance means the frequencies
match. If the frequency of energy and the frequency of matter match, they
are in resonance and the energy combines with the matter. Resonance, or
frequency matching, is merely an aspect of heterodyning that enables the
coherent transfer and combination of energy with matter.
So in our example above with the wire and atoms, we could have
created resonance with the atom. and transferred energy to it directly. by stimulating it with a laser exactly matching its NOF. We would be
53/' Page -8~ J;f!JJ3•/,;2-/if-
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energizing it with its· resonant frequency. Or, as the clever scientists did \Vho perfonned the experiment, we could take advantage of the heterodyning that naturally occurs between frequencies of energy and matter. We can produce the resonant frequency of the atom (NOFatom) indirectly, as an additive (or subtractive) heterodyned frequency, between the resonant frequency of the wire (NOFv.m:) and the frequency of the laser. Either direct resonance, or indirect resonance through heterodyned frequency matching produces resonance and combining of the matter and energy.
Another indirect form of resonance not used by the scientists in that experiment is quite familiar to music lovers in the form of harmonics. A harmonic is a frequency that is an integer multiple of the resonant (NOF) frequency. For instance, we can play the note "A" at 440 Hz. If we double that frequency to 880 Hz. we will play "'A'' an octave higher. This first octave is called the first harmonic. Doubling our note or frequency again, ".Jrom 880 Hz to l 760 Hz (four times the frequency of the original note) gives ::i1s another "A", two octaves above the original note. This is called the third :\~armonic. Every time you double the frequency you get another octave, so i:'.~hese are the even integer multiples of the resonant frequency. '" In between the first and third harmonic is the second harmonic, which ;.,::is three times the original note. This is not an octave like the first and third
0
;, harmonics. It is an octave and a fifth, equal to the second "E" above our ;:;:roriginal "A". All of the odd integer multiples are fifths, rather than octaves. i::,-;Because harmonics are simply multiples of the fundamental natural !:,;=oscillatory frequency, they stimulate the NOF or resonant frequency :::':indirectly. Play the high "A" at 880 Hz on a piano, and the string for middle ,,,,"A" at 440 Hz will also begin to vibrate.
Matter and energy in chemical reactions respond to harmonics of resonant frequencies much the way musical instruments do. We can stimulate the resonant frequency of the atom (NOFatom) indirectly, using its' harmonics. This is because the harmonic frequency heterodynes with the resonant frequency ofthe atom itself(NOFatom). Say, for instance our laser is tuned to 800 Thz and our atom resonates at 400 Thz. Heterodyning the two frequencies gives us:
800 Thz - 400 Thz = 400 Thz.
The 800 Thz (the atom's first harmonic), heterodynes with the atom· s own resonant frequency, to produce the atom's own resonant frequency. Thus, the
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first harmonic indirectly resonates with the atom's NOF, and stimulates the atom's resonant frequency as a first generation heterodyne. -
Of course, the two frequencies will also heterodyne in the other
direction, producing:
800 Thz .... 400 Thz = 1,200 Thz.
The 1,200 Thz frequency is not the resonant frequency of the atom. Part of the laser's energy will heterodyne to produce the resonant frequency of the atom. The other part of the laser's energy heterodynes to a different frequency, that does not itself stimulate the resonant frequency of the atom. That is why the stimulation of an object by a harmonic frequency of particular strength or amplitude, is always less than the stimulation by its' own exact resonant (NOF) frequency at the same strength. "'"' The preceding discussion highlights the fact that the same fundamental ::;;iprocess ofheterodyning governs all the interactions of matter, energy, and :\,~their combinations. It was this very similarity in process that prompted /:~~Albert Einstein to write several important papers in 1905 modeling atomic it,events using statistical methods of chemical dynamics. His papers provided :::1~the springboard for the later development of relativity and quantum theories. ::· One of these papers described interactions of energy with matter in his :;:~explanation of the photoelectric effect5. He postulated that electromagnetic energy (ie. a beam of light) was made up of small packets of energy, called
photons. Based on the photon concepts in his landmark paper, textbooks now teach that the energy E of a photon is related to its' frequency f, by the
equation,
E = hf,
in which h is a universal constant, called Planck's constant. When a packet or photon of electromagnetic (EM) energy strikes an atom, it may transfer its energy to the atom if their frequencies match. Then the photon ceases to exist as an individual packet of energy. It blends and merges with the electron cloud of the atom, just like a spoonful of water blending into a cup of water.
'Einstein A: On a Heuristic Point of View Concerning the Production and
Transfonnation of Light: Annalen da Physzk. l9 0 5 ~
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Einstein believed that quantum mechanical descriptions were not the
whole story, and that they might someday be replaced by a more complete
theory. Over his objections, his energy quanta theories were used to develop
theories in which the entire concept of the quantum state was inherently
statistical. He is often quoted as cautioning. "God does not play dice with the
universe." There may yet be good reason to heed that admonition.
- The
original
intent
of
his
work
\\as
misunderstood
bv ~
manv. .
Take for
example the modern definition of a photon. Current science teaches that the
energy of a photon is equal to Plank's constant multiplied by the frequency.
Thus. the higher the frequency, the higher the energy. Textbooks are full of
examples and explanations of scienti fie phenomena based on ''high frequency
photons'' having high energy, as opposed to "low frequency photons" with
lower energy by comparison.
But Planck's constant and photon frequency are both arbitrarily defined
in
units
of Joule·seconds
and
seconds·
1 ,
respectively
\Vhen multiplied, the
::~:econds cancel out and a unit of energy is obtained. The unit of energy,
i;J,jowever, is merely the amount of energy in one second's worth of EM
!,waves. If one calculates the amount of energy in one wave of EM energy, it
;;~ms out that all EM energy has the exact same amount of energy per wave,
::~o matter what the frequency (Appendix B). High frequency EM energy has
~:the same amount of energy in one wave, as low frequency EM energy has.
••
The "high energy photons" simply fit more waves into a second than
;Jjhe low energy photons. Naturally, if all waves have the same amount of
Cinergy, and you double the number of waves, you will double the energy.
:;2[he whole concept of photons with different amounts of energy is an artifact
1"Which detracts from an understanding of the processes around_ us.
So what is going on around us in the process of chemical reactions?
Ostwalds's theories on catalysts and bond formation were based on the
kinetic theories of chemistry from the turn of the century. We know quite a
bit more than Ostwald did when he proposed his theory. We now know that
chemical reactions are interactions of matter, and that matter interacts '"'ith
other matter through heterodyning of frequencie?. We know that energy can
just as easily interact with matter through this same process of heterodyning.
With the advent of spectroscopy (more on that later) we also learned that
matter produces electromagnetic energy at the same frequencies at which it
vibrates. Energy and matter move about and recombine with other energy or
matter. depending on their frequencies. In many respects. both
philosophically and mathematically, both matter and energy are frequency.
This leads to the inescapable conclusion that since chemical reactions are recombinations of matter driven by energy, they are in effect~ driven just as much by frequency.
Well, this all sounds well and good, but if we analyze a reaction, is this what is really going on? Actually, it is. And a good reaction to look at is the formation of water from hydrogen and oxygen gases, catalyzed by platinum. Platinum has been known for some time to be a good hydrogen catalyst, although the reason for this has not been well understood.
Pt
This reaction is proposed to be a chain reaction, dependent on the generation and stabilization of the hydrogen and hydroxy radicals. The j 1proposed reaction chain is:
-+-+--+-..-+--+-+_.
½H..
1
H
i
1
i
H + 0 2 + H2
i
1
T
H..O + OH·
T
1
T
OH·+ H2
T
1
Creation and stabilization of the hydrogen and hydroxy radicals are
thought to be crucial to this reaction chain. Under nonnal circumstances,
- h.v, drog......en
and
oxvgen -''-"
gas
can
be
mixed
together '-"
in
a
container
indefinitelv., .
and thev., do not form water. \\'henever the occasional h.vdro-g-en molecule
splits apart. the hydrogen atoms do not have enough energy to go out and
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react with an oxygen molecule. They simply bond with each other again into
another hydrogen molecule.
The trick to catalyzing this reaction is to energize and stabilize the
hydrogen intermediates, so they can react with oxygen to form hydroxy
- intermediates.
Then
vou
.,/
energize
and
stabilize
the
h.v,, droxy.
intermediates
so
they can react with more hydrogen molecules. Eventually you end up with
\Vater from a chain reaction. How do \Ve stabilize and energize intermediates
such as these? The same way nature does - increase their energy levels. Of
course we already know that the energy levels of matter can be increased by
energy with a matching frequency. In other words, we can stabilize the
intermediates by producing resonance with them. Interestingly, that is
exactly what platinum does. And in the process of stabilizing the reaction
intermediates, platinum allows the reaction chain to continue, and thus
catalyzes the reaction.
By now, you are probably wondering just how platinum produces
resonance \vith the reaction intermediates. Quite naturally, it does it by
taking advantage of all the ways frequencies interact with each other.
Frequencies interact with each other and create resonance either: 1. directly,
by exactly matching the frequency; or 2. indirectly, by heterodyning to match
the frequency. In other words, platinum vibrates at frequencies which both
directly match the natural oscillatory frequencies of the radicals, AND which
indirectly match the radical frequencies by heterodyning with the radicals.
The hydroxy radical is a good example of how platinum directly
matches the frequency to produce resonance. Hydroxy radicals vibrate
strongly at frequencies of 975 THz and 1,060 THz. Platinum also vibrates at
975 THz and 1,060 THz. By directly matching the frequencies of the
hydroxy radical, platinum can cause resonance in the hydroxy radical,
enabling it to energize and stabilize long enough to take part in chemical
reactions.
Hydrogen gives us a good example of matching frequencies by
heterodyning. A little background history is in order here. In 1885 a fellow
by the name of Balmer discovered that hydrogen vibrates and produces
energy at frequencies in the visible light region of the electromagnetic
spectrum which can be expressed by a simple formula,
where A is the wavelength of the light, R is Rvdberg's constant, and mis an
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integer greater than or equal to 3 (ie. 3, or 4, or 5, etc.) A few years later,
Rydberg discovered that this equation could be adapted to give all the \vavelengths in the hydrogen spectrum by changing the 1/22 to l/n2, as in,
where n is any integer 2: 1, and m is an integer 2: n + 1. For every different number n, you ended up with a series of numbers for wavelength, and the names of various scientists were assigned to the series. For instance, when n=2 and m;?:3, the energy is visible light and the series is called the Balmer series. The Lyman series is in the ultraviolet with n=l, and the Paschen series is in the infra-red \vith n=3.
These early scientists found the units of frequency difficult to work \Vith, so they did everything in wavelengths (A) and wavenumbers (which are the inverse ( 10.) of wavelength.) By the time Einstein and Schrodinger were :.i!,~one, they had gone to using energy level diagrams to describe all this. (See iiFigure 7., for energy level diagrams of the hydrogen atom)6. People did not u*hink about the actual frequencies anymore. Instead, all the interest was in ::i'.}vavefunctions, energy levels, orbitals, quantum numbers, and Hamiltonians. l\J.fhat was unfortunate, because this switch in nomenclature caused scientists :::·'.to miss some of the really fun things going on between matter and energy.
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Figure7. - Hydrogen energy Ie,·el diagrams
~ .-\tomic Spectra: Softley TP. Oxford Sci Publ. 199➔ & Atomic Spectra: Johnson RC.
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Take a glance at what hydrogen looks like when we ta~e the very same
infonnation used to make energy level diagrams, and graph the actual
frequencies and intensities instead (Figures 8.-10.) The X axis shows the
frequencies produced by hydrogen, while the Y axis gives the relative
intensity for each frequency. The frequencies are plotted in terahertz (10 12
Hz) and are rounded to the nearest Thz. The intensities are plotted on a
relative scale of l to l ,000. The highest intensity frequency that hydrogen
atoms produce is 2466 Thz. This is the peak of the curve to the far right. We
will call this the first curve. It sweeps down and to the right, from 2466 Thz
at a relative intensity of 1,000, to 3237 Thz at a relative intensity of only l 5.
The second curve starts at 456 Thz with a relative intensity of 300, and
sweeps down and to the right. It ends at a frequency of 781 Thz, with
relative intensity of 5. Every curve in hydrogen has this same downward
sweep to the right. Progressing from right to left, we number the curves I
t1,~••1 hrough V; going from high to low frequency, and from high to low intensity. ;;~The reason for this backwards numbering will be apparent momentarily.)
.,
The hydrogen frequency chart really gives you quite a different feel for
1
;::;fthe hydrogen atom, and looks a lot simpler, than the energy level diagram
:;r1with all the arrows going this way and that. It is easy to visualize how the
:;;frequencies are organized into the different curves. In fact, there is one curve
;;·- for each of the series described by Rydberg. The big curve farthest out to the
::;!right - curve I - contains the frequencies in the Lyman series, originating
i'.::rrom what quantum mechanics calls the first energy level. The second curve
i"i'from the right - curve II - equates to the second energy level, and so on.
Now the interesting thing about the curves in the hydrogen frequency
chart is that they are composed of additions and subtractions. Take, for
instance, the smallest curve at the far left, labeled curve V (Figure 9. -
Magnification of lower hydrogen frequencies). Curve V has two frequencies
in it, 40 Thz and 64 Thz, with relative intensities of 6 and 4, respectively.
The next curve - IV - starts at 74 Thz, goes to 114 and ends with 138 Thz.
The additions go like this,
40 + 74 = 114
64 + 74 = 138.
The frequencies in curve IV are the sum of the frequencies in curve V plus the peak intensity frequency in curve IV.
1000
750
l{elativc Intensity
500
• , ..-1-- r ..,1 .,1·;, 1:··· .,,t ''''" t ,,,,, t,". ,,;i,, 1;;;l 'fl,il '""
,
~
I\
'
' ~
l\
250
~-
\
- 1t.
~
~ .~ ....,
~
\
II
\
"
t
~
'"
I
m.1111 ii.I IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIBtt 11111
500
1000
1500
2000
2500
Frequency (Thz)
Figure 8. - Frequency diagram of hydrogen
Page -16-
3000
3500
50
,.I
Rel.
-
Int.
' I\.
'
'
1,
25
-I', ,i
' ...
I "
~
.
0
0
¥
""" ..
50
ro ... _...
...
-
100
150
200
250
300
350
Frequency (Thz)
Figure 9. - Magnification of lower hydrogen frequencies
Figure 10. - Frequencies and intensities for hydrogen Frequency Curves -Thz (relative intensity)
V
IV
II
I
40 (6) 64 (4)
74 (15) 114 (8) 138 (5)
160,(40) 234 (20) 274 (12) 298 (7) 314(5)
456 (300) 616(80) 690 (30) 731 (15) 755 (8) 770 (6)
781 (5)
2466 (1000) 2923 (300) 3082 ( l 00) 3156 (50) 3196 (30) 3220 (20) 3236 (15)
Page -17-
Another way of looking at it is that the frequencies in c_urve IV. minus the frequencies in curve V, yield the peak of curve IV:
114 - 40 = 74~
138 - 64 = 74.
This is not just a coincidental set of additions or subtractions in curves IV
and V. Every curve in hydrogen is the result of adding each frequency in any
one curve, with the highest intensity frequency in the next curve.
These hydrogen frequencies are found in both the atom itself, and in
the electromagnetic energy it radiates. The frequencies of the atom and its
energy, add and subtract in regular fashion. Remember what adding and
subtracting of matter and energy is? It is heterodyning. So, not only do
- matter and energ._.y. heterodv., ne interchanQ.._,:eabl.v, but matter heterodvnes its'
:T:own energy within itself.
•,,.
It doesn't stop there either. Wonder where the peak frequencies come
from? They are heterodynes of heterodynes. Look at the peak frequency in
i"; the biggest curve, the one at the farthest right, curve no. I. The frequency is
2,466 THz. Divide 2,466 by 4 and you get 616 THz,
2,466 Thz ~ 4 = 616 Thz, or, 4 X 616 THz = 2,466 THz.
Let's talk about the 4 part first. We already know from our discussion about heterodyned frequencies and harmonics, that you end up with even multiples of the starting frequency (from 400 we got the first harmonic at 800 (400 X 2), and the third harmonic at 1,600 (400 X 4)). The even integer multiples are octave harmonics. Multiplying a frequency by four (4) is a natural result of the heterodyning process. This means that 2,466 THz is the
third harmonic of 616 Thz. It is a second generation heterodyne - a two octave harmonic of 616 Thz.
The peak of curve II, frequency 456 Thz, is the third harmonic of 114 Thz in curve IV. The peak of curve III, frequency 160 Thz, is the third harmonic of 40 Thz in curve V. The peaks of the curves are heterodynes
between the curves, and are also harmonics of individual frequencies.
OK, so 2.466 Thz is a harmonic of 616 Thz. What about 616 Thz?
\Vell. it results from the addition of 456 and 160. But 456 is itself a heterodyne and harmonic. and so is 160. \\'hat you end up with is the
situation that the biggest highest intensity frequency in the entire hydrogen
f:ffJJJ~--/~-~
Page-18~
0Pf (1/r-r(ff
spectrum. namely 2,466 THz, is a second generation heterodyne of some eighth and ninth generation heterodynes. The whole hydrogen spectrum turns out to be an incestuously heterodyned set of frequencies and harmonics.
All this heterodyning and harmonizing has an interesting effect. Look at the intensities of the curves as you move from low to high frequencies, from curve V to curve I. The intensities increase - a lot. The heterodyned frequency curves amplify the vibrations and energy of hydrogen. In many respects. the hydrogen atom is just one big energy amplification system.
Vie know what the highest set of frequencies is for hydrogen, but what about. the low end? Theoretically, this heterodyne process could go on forever. If 40 is the peak of a curve, that means it is 4 times a lower number,
and it also means that the peak of the previous curve is 24 (64-40 = 24). It is
possible to mathematically extrapolate backwards and downwards this wq.y to derive lower and lower frequencies. Peaks of successive curves to the left are ,;,4.238:!, 15.731. and 10.786 Thz- all generated from the heterodyne process. ;~hese frequencies are in complete agreement with the Rydberg formula for l~;nergy levels 6, 7, and 8, respectively. Not a lot of attention is given these ilow frequencies. They just are not as exciting as the higher intensity :(requencies. ''· • This may all seem somewhat far afield, but it turns out to have a direct £earing on platinum, and on how platinum interacts with hydrogen. It all has
:!9 do with hydrogen being an energy amplification system. It is like money
rJ'n the bank. Put a dollar in the bank today, and you will have one dollar in ;:ttie bank. But if you had put a dollar in the bank back in 1835, when
;~@erzelius proposed the catalytic force, you would have hundreds of dollars today. Just so, stimulate hydrogen with 2466 Thz at 1000 intensity and you will have 2466 Thz at 1,000 intensity. But if you stimulate hydrogen with 40 Thz at 1,000 intensity, by the time it is amplified back out to curve I, you will have 2466 Thz at 167,000 intensity.
Understood this way, those low frequencies of low intensity suddenly look very interesting. Extend the hydrogen spectrum back to I0.786 Thz, and then compare the hydrogen frequencies to the platinum frequencies. You will find that many of the platinum frequencies are direct matches or multiples (harmonic heterodynes) of the hydrogen frequencies (Appendix A). Seventy frequencies of platinum (40%) are resonant or harmonic frequencies of at least 19 frequencies of hydrogen (80%). Platinum causes massive r~sonance in the hydrogen atom.
A further look at the individual hydrogen frequencies is even more
- (/fTf?J /cJ-/C(-~ Paee -19-
1 ; ,J~ I /1,(.., {11
inforn1ative. Platinum resonates with most, if not all of the hydrogen frequencies with one notable exception, the highest intensity curve at the far right in the frequency chart, curve I representing energy level 1, and beginning with 2,466 Thz. Platinum does not resonate with the ground state of the hydrogen atom. It resonates with the lower frequencies in the upper energy levels.
\Vith that little bit of information we have solved an ongoing mystery in physical chemistry. Ever since lasers came out the physical chemists had a hunch that there had to be some way to catalyze a reaction using lasers. They decided that the highest intensity frequency of an atom (such as 2,466 Thz of hydrogen) would give them the biggest bang for the buck. If you are just looking at energy level diagrams it makes sense. So they have been tuning their lasers ever since to the ground state frequencies. Not surprisingly, their experiments have been minimally successful in catalyzing reactions.
Of course, platinum, the quintissential hydrogen catalyst, does not resonate with the ground state of hydrogen. It resonates with the upper energy level frequencies - lots of them. Perhaps this is why platinum is such a good hydrogen catalyst. The hydrogen atom acts as a big energy amplification system. A little bit of energy, at a low frequency in a high
energy level, can go a long way. By the time it works its way from curve IV
or V, back out to curve I, it can have tremendous intensity and really shake things up. So that is how such a small amount of catalyst can have such a profound effect - by resonating with upper energy levels of its target.
Most of the attempts of the last forty years to catalyze reactions with lasers have used one frequency from the reactant'sfirst energy level. But platinum does not do this. It resonates with many frequencies from the upper energy levels (lower frequencies). There is a name given to the process of stimulating many upper energy levels - it is called a laser.
Einstein worked out the statistics on this at the turn of the century7. Take a bunch of atoms at the ground energy level (E,) and resonate them to an excited energy level (E2). Call the number of atoms in the ground state N 1 and the number of excited atoms N 2, with the total Ntota1· Since there are only two possible states the atoms can occupy:
If you go through all the mathematics using temperature (kelvin) and the Boltzmann constant, you arrive at:
<
Ntotal
NI+ N2
2
In a t\vo level system there 1w:ill never be more than 50% of the atoms in the
higher energy level, E2, at the same time.
. IC however, vou take the same bunch of atoms and energize them at ~
three (3) or more energy levels (a multi-level system), it is possible to get
more titan 50% of the atoms energized above the first level. Call the ground
and energized levels E1, E2, and E3 respectively, and the numbers of atoms N101a1, N1, N2, and N3 • Under certain circumstances, the number of atoms at
energy level 3 (N3) can be more than the number at the second energy level (~:J• \\'hen this happens, it is called a '"population inversion''. Population
::!lnversion means that more of the atoms are at higher energy levels, than at i:;Jower levels .
..,, What is so special about a population inversion? It causes amplifica-
;;ition of light energy. In a two-level system, if you put in one photon, you get
::!~ne photon out. In a system with 3 or more energy levels and population '.:"inversion, if you put in one photon, you get out 5, I0, or 15 photons (Fig. 11
:::;below). It all depends on the number of levels and just how energized you
;::get them. All lasers are based on this simple concept of producing a
j,,,ipopulation inversion in a group of atoms, by creating a multi-level energized 1;~~ystem amongst the atoms. Lasers are simply devices to amplify :,"~lectromagnetic wave energy (light). Laser is actually an abbreviation for
Light Amplification System for Emitting Radiation.
hv
~
eeFORE
AFTER
• ablolpffol,
• • spoi Ila l80.JI 8"'.aia,
hv
~
hv
""-IV'+
• lfimulated emilicn
Two level svstem
Multi-level svstem
Figure 11 8.- Light amplification \\ ith stimulated ernission/pop.ulation inversion
8 Sr,l:'cm.1 of .--\toms and ~tolecuks: Bernath PO~'\f .d L'niv. Pre~~95~
Page •21·
ldJ-/< o/ kjr.J 11f1/tr1;_1
This takes us back to platinum and hydrogen. Platinum .energizes 19 frequencies in hydrogen (80% of the total hydrogen frequencies). We only need three frequencies for a population inversion. Hydrogen is stimulated at
19! This is a multi-level system, if ever there was one. Next consider that
seventy platinum frequencies do the stimulating. On average, every hydrogen frequency involved is stimulated by 3 or 4 (70/19) different platinum frequencies - both direct resonant and/or indirect resonant hannonic frequencies. Platinum provides ample stimulus, atom per atom, to produce population inversion in hydrogen. Finally, consider the fact that every time a stimulated hydrogen atom emits some electromagnetic energy, that energy is of a frequency that matches and stimulates platinum in return.
Platinum and hydrogen both resonate with each other in their respective multi-level systems. Together,, platinum and hydrogen fonn an atomic scale laser - an energy amplification system on the atomic level. In so ,,vpoing, they amplify the energies that are needed to stabilize both the ;;~hydrogen and hydroxy intermediates, thus catalyzing the reaction. Platinum !'~is such a good hydrogen catalyst, because it forms a lasing system with i'.:a1ydrogen on the atomic level, amplifying their respective energies. ,., , OK, so now we know how platinum catalyzes reactions. Getting back ::!ito our original discussion of matter heterodyning, this seems to be a basic ::, matter:matter interaction. An atom of platinum interacts with an atom of
01
::;~pydrogen or a hydroxy radical. And that is exactly what modem chemistry ::~has taught for the last one hundred years, based on Ostwald's theory of ;:::;catalysis. The modem textbooks teach that catalysts must participate in the E1reaction by binding to the reactants, in other words, they teach a
matter:matter interaction is required for catalysts. This is taught in the following steps:
I. Reactant diffusion to the catalyst site; 2. Bonding of reactant to the catalyst site; 3. Reaction of the catalyst-reactant complex; 4. Bond rupture at the catalytic site (product); and 5. Diffusion of the product away from the catalyst site. But Ostwald's theory of catalysis was formulated before lasers were ever built. That had to wait for AT&T in 1958. Fortunately, there have been many scientific advances since that theory of catalysis was first formulated. \Ve now know, for instance~ that energy:energy frequencies can interact. as
~/.;t~So. we! l as energy:matter frequencies. We also know that matter radiates energ~.
with the energy frequencies being identical ~ ;
1
Page - 2 : - ~
/r, µfl J ft/r1
platinum vibrates at the frequency of 1,060 THz, and it also radiates electromagnetic energy at 1,060 THz. Once you start looking at it this way, the distintion between energy frequencies and matter frequencies starts to look less and less important.
We can produce resonance in the reaction radicals by letting them come in contact with another bit of matter vibrating at the same frequencies, such as a platinum atom. This is consistent with the current theory of catalysis by Ostwald. Or (and here is the interesting part) \Ve can produce resonance in the radicals by zapping them with just the platinum energy, which also vibrates at the same frequencies. Matter, or energy, it makes no difference as far as the frequencies are concerned. So we don't need the actual physical catalyst to speed up a reaction. Its energy pattern and frequencies will do just fine. In other words, you can duplicate the action of the catalyst, by duplicating its energy frequencies.
Think back to our reaction combining hydrogen and oxygen gases, to ;produce water. Traditionally, that is done with a physical platinum catalyst. !'~e can also catalyze the reaction using only the energy pattern of platinum. ::This is not a physical catalyst, in the true sense. It is a different kind of 1;~atalyst. An energy field that duplicates frequency(s) from a physical catalyst :,~s called a spectral catalyst. '~"· The name "spectral" comes from the field of science concerned with :;:~easuring the frequencies of energy and matter. That field is called ;::;pectroscopy, and the pattern of energy or electromagnetic frequencies !::~mitted or absorbed by an atom or molecule is called its spectral pattern, or ;!~pectrum. So, for the purposes of keeping things straight from here on out, whenever we are talking about the matter:matter interaction of catalysts in the standard chemical theory sense, we will call that a "physical catalyst", because it is physically present as matter in the reaction. And whenever we are referring to the electromagnetic energy (ie. spectral) pattern of a catalyst, we will call that a "spectral catalyst."
The field of spectroscopy actually has much to teach us about how matter and energy vibrate. The spectra of atoms and molecules are broadly classified into three (3) different groups - electronic, vibrational, and rotational. The electronic spectra are said to result from transitions of electrons from one energy level to another, and have the highest frequencies, occuring in the ultraviolet (lN). visible, and infrared (IR) regions of the ENI spectrum. Electronic spectra occur in both atoms and in molecules.
The vibrational spectra are said to result from stretching of bonds
/c/2- ;9- Page -23-~
~ J (1/rrftr
between individual atoms within molecules. An example of t~is would be
the vibrational spectra resulting from the various stretching modes of the
h.v,
d
rogen "-"
atoms
attached
to
oxv., g......en,
in
the
water
molecule.
Vibrational
spectra can occur only in molecules, because by definition they must occur
between bonded atoms. This means that atoms such as hydrogen and
platinum do not have vibrational spectra - they have only electronic spectra.
Vibrational frequencies are generally in the IR region.
Lastly, rotational spectra occur chiefly in the micro\vave or radiowave
regions of the EM spectrum, and are thought to result from rotation of
molecules in space. As a result, a gas phase is necessary to support
generation of a traditional rotational spectrum. Molecules found only in solid
or liquid phases are generally not able to rotate freely in space, and thus do
not produce rotational spectra.
Interestinglv, "-'.,
some
atoms
and
molecules
normallv.,,
found
in
onl.v,
solid
,Tt°r liquid phases (such as metals) produce microv;ave and radiowave
;!:frequencies anyway. These frequencies tend to vary with the size and shape
:lfof the substance, and are thought to be antenna-type transmitter effects, rather
;::-~,than true rotational frequencies. Because these antenna frequencies are not
;;[~rotational frequencies in the classical sense, many people dismiss their
::~;importance. Never-the-less, they are probably important to the subject of
,;-·catalysis and chemical reactions.
,,, The various spectral modes do not act in isolation from each other.
:'.:~::stimulation in one spectral mode, can lead to excitation in another mode. For
:;:;,'example, if water is stimulated with its' rotational microwave frequency, it
;,:::;will also become stimulated in its vibrational and electronic modes, albeit to a
---- lesser extent. If sufficiently powerful, a rotational stimulus can produce a
vibrational or electronic transition. Thus there is an interlocking continuum
of effects between rotational, vibrational, and electronic energy transitions of
molecules, and the atoms of which they are composed.
Whenever we talk about a spectral catalyst duplicating any of a
physical catalyst's energy pattern, we are referring to all the different
frequencies produced by a physical catalyst; including electronic, vibrational,
rotational, and antenna frequencies. To catalyze, control, or direct a chemical
reaction then, all we need to do is duplicate one or more frequencies from a
physical catalyst, with an energy field. The actual physical presence of the
catalyst is not necessary. A spectral catalyst can replace a physical catalyst.
.-\ spectral catalyst can also augment or promote the activity of a
physical catalyst. The exchange of energy at particular frequencies, between
~j}~/~
Page -2➔- { r
µf J /lj'tfr"r
hydrogen. hydroxy. and platinum is what drives the conversion to water.
Platinum and hvdrogen interact and create a minature atomic scale lasing
..
........
i...,,
system that amplifies their energies. The addition of these same energies to a
reaction system, using a spectral catalyst, does the same thing. It amplifies
the hydrogen and platinum energies by adding to them. Thus, a spectral
catalyst can augment a physical catalyst. as well as replace it.
--close onl~ counts in horseshoes :md hand grenades:· .-\non~mous.
Horseshoes and Harmonics Some things in life are all or none phenomena. Being pregnant is one
of those things: you either are, or you aren ·t (pregnant that is.) In other endeavors. such as horseshoes and h'and grenades. being right on target is nice, but it is also good just to be close. Resonance and heterodyning of energy and matter are like horseshoes and hand grenades. Being right on the target frequency is ideal, but being close to the target frequency can also produce some powerful effects.
Take for example, the effects of platinum on the hydroxy radical. Hydroxy radicals vibrate strongly at frequencies of 975 THz and 1,060 THz. Platinum also vibrates at 975 THz and 1,060 THz. By directly matching the frequencies of the hydroxy radical. platinum causes resonance in the hydroxy radicals, stabilizing them long enough for them to take part in the chemical reaction which leads to the formation of water.
We can duplicate platinum's stabilizing effects on the hydroxy radical by using lasers tuned to 975 Thz and 1,060 Thz. But what if our lasers could only be tuned to 972 Thz and 1,070 Thz? Would our lasers still stabilize the " hydroxy radicals? The answer is yes. This is because of the resonance qualities of objects and matter.
All objects, be they atom or elephant have resonant frequencies, their natural oscillatory frequencies. Energy which either directly matches, or matches via heterodyning with the NOF (resonant frequency) of the object will transfer to and combine with the object. The more exact the match, the more energy will transfer. If we use energy waves to exactly and directly match the resonant frequency of an object then a lot of energy will transfer and combine with the object. If the frequencies are just slightly different, then slightly less energy will transfer. If the frequencies are more different, then even less energy will transfer. Finally, one reaches a point where the frequencies are so different that essentially no energy transfers at all.
This can be shown by a simple diagram (Fig. 12 below). It is a basic bell-shaped curve produced by comparing how much energy an object absorbs, with the frequency of the energy. It is called a resonance curve.
The energy transfer is maximal at the resonant frequency(() The farther
you get from the resonant frequency, the lower the energy transfer. At some
Page -26~;:;J- -/c,/-';7~
Jt f ( 7/r'1('tf
point the energy transfer will fall to only 50% of that at the r·esonant frequency. The frequency above the resonant frequency, at which energy transfer is only 50% is called t~. The frequency below the resonant frequency. at which 50% energy transfer occurs, is called f1.
.-\mplitude :
Frequency ➔
Figure 12. Resonance curve. (f0 = resonant frequency. t~ = upper frequency at 50% amplitude.
:;;;;:and f1 = lower frequency at 50% amplitude.)
The resonant characteristics of different objects can be compared using the information from this simple resonance curve. One of these useful characteristics is called the "resonance quality" or "Q" fa<;tor. To find out what the resonance quality is for an object we calculate:
Q=
If the bell-shaped resonance curve is tall and narrow, then (f2 - f1) will be a very small number and Q, the resonance quality, will be high (Fig.
13.a.). This would be the case with a good quartz crystal resonator. If the
resonance curve is low and broad, as would be the case for a marshmallow, then the spread or difference bet\veen f2 and f1 will be very large. Dividing the resonant frequency by this large number will produce a much lower Q \·alue(Fig.13.b.).
..\mplitude :
Frequency ➔
a) Resonance curve \\ith high Q
Amplitude:
Frequency ➔
b) Resonance curve with low Q
. Figure 13. Resonance curves with different resonance quality factors. Q. a) Narrow resonance curve with high Q; b) Broad resonance curve with low Q. (Q = f0 I f2 • f11 )
All this talk of Q values may seem a bit far afield, but is does relate back to our horseshoes example. Atoms and molecules have resonance curves just like larger objects such. as quartz crystals and marshmallows. If you want to stimulate an atom (such as hydrogen in our reaction) you can use an e:\act resonant frequency produced by hydrogen. You don·t have to use
that exact frequency hov,:ever. You can use a frequency that ·is merely close
to a hydrogen resonant frequency. There will not be quite as much of an
effect as using the exact frequency, because les·s energy will be transferred,
but there will still be an effect. The closer you are to the resonant frequency,
the more the effect. The farther away you are from the resonant frequency,
the less effect you \\ ill see. So as v. ith horseshoes and hand grenades,
chemical
reactions
are
great
~
if .vou
are
right ~
on
target ~
with
a
resonant
frequency, but it is also good just to be close.
Hannonics present a similar situation. They are created by
heterodyning (adding and subtracting) of frequencies. Take our imaginary
atom vibrating at -+00 Thz and expose it to 800 Thz electromagnetic energy.
The frequencies \vill subtract and add:
800 Thz - -+00 Thz = -+00 Thz
And
800 Thz + 400 Thz = 1200 Thz.
In this first generation heterodyne, at most only 50% of the energy appears to resonate with the atom's frequency of 400 Thz. The other 50% of the energy goes into producing 1200 Thz and looks like it is wasted. Viewed this way, harmonics appear to be rather inefficient means of stimulating resonance.
The energy transfer from a harmonic is actually quite a bit more than 50% however. We must look beyond the first generation heterodyne to other generations to understand this. The 1200 Thz heterodyne for which 50% of the energy seems wasted, will heterodyne with other frequencies also, such as 800 Thz, and:
1200 Thz - 800 Thz = 400 Thz.
Also, the 1200 Thz will heterodyne with 400 Thz:
1200 Thz - -+00 Thz = 800 Thz,
producing 800 Thz~ and the 800 Thz will heterodyne with -+00 Thz:
800 Thz - 400 Thz = 400 Thz.
producing 400 Thz again. When other generations of heterodynes of the
seemirnzlv wasted enern:v are taken into consideration, the amount of enerov
._ "'
.._..,
e ...
transferred by a first harmonic frequency is much greater than 50%. It is not
as much as the energy transferred by direct resonance. but it is still enough to
produce a noticeable effect. (Fig. 14.) In this regard. hannonics in chemical
reactions are also like horseshoes. Being right on target with a resonant
frequency is nice, but a harmonic is also good.
Fundamental resonant frequency curve
Amplitude:
Frequency ➔
Figure 14. Energy transfer at fundamental resonant frequency using resonant frequency and harmonic frequency.
The last situation we consider is a harmonic horseshoe. In other words, if a resonant effect is produced: 1) by being close to the resonant frequency; or 2) by being a harmonic of the resonant frequency; is it possible to produce an effect simply by being close to the harmonic frequency? The answer is yes. The amplitude of the energy transfer will be less on both accounts, but you will still produce an effect. For example, say the harmonic produces 70% amplitude of the fundamental resonant frequency. You are also using a frequency which is merely close to the harmonic, at 90% on the harmonic's resonance curve, then your total effect will be 90% of 70%, or 63% total effect.
Duplicating the Catalyst 1'-lechanism of Action
Some of the best ideas in science come from copying nature.
Antibiotics are a good example of the success that can be achieved by
copying nature. Dr. Alexander Fleming, the discoverer of antibiotics, had a
messv. laboratorv. . Some fung.._.us .g._,ot into his bacteria culture dishes and
''contaminated" them. Fortunatelv. for modem medicine, the .g...ood doctor
noticed that no bacteria were .g... rowing.... around the fung--us. He soon learned
that the fungus produced a substance that killed bacteria, and that he could
copy the fungus mechanism of action and kill bacteria in sick people by using
antibiotics. Since then, an entire science of antibiotic pharmacology has
grown up around the simple concept of duplicating nature's processes.
We can apply this same simple concept to extend our control over
chemical reactions. In many respects. the spectral catalyst itself is a result of
this simple concept. To catalyze, control, or direct a chemical reaction, we
need only duplicate one or more frequencies from a physical catalyst. The
actual physical presence of the catalyst is not necessary. This is
accomplished by understanding the underlying mechanism inherent in
catalysis - namely the exchange of energy at certain frequencies. In other
words, we copy the mechanism that nature has built into the catalytic process.
The result is spectral catalysts.
Can we apply the simple concept of copying nature yet again to control
reactions? The answer is yes. A closer look at the catalyst process reveals
several opportunities for duplicating catalyst mechanisms of action, and
hence improving our spectral catalysts and our control of chemical reactions.
For example, consider our reaction with hydrogen and oxygen
producing water, using platinum as a catalyst. In the Background section we
learned that platinum accomplishes this task several ways:
l. It directly resonates with and energizes reaction intermediates
(atomic hydrogen and the hydroxy radical);
2. It hannonically resonates with and energizes a reaction intermediate
(atomic hydrogen);
3. It energizes a reaction intermediate at multiple upper energy levels,
setting up an atomic scale laser system (atomic hydrogen).
Can we take advantage of this knowledge to improve our catalyst
systems? Yes! The frequencies of atomic platinum are in the ultraviolet,
visible light. and infra-red regions of the electromagnetic spectrum. The
electronic spectra of all atoms are in these regions. These very high
electromagnetic frequencies produce a bit of a problem for large-scale and
~
Page-.)
l
(tY?J-ll)•;
9
✓Cf;:_~
t-JI f
(1-/r't(y 7
industrial applications. \\'a\ e energies of very high frequency do not penetrate matter very well. The tendency of a wave energy to be absorbed rather than transmitted, is called attenuation. High frequency wave energies have high attenuation. They \vill not penetrate deeply into an industrial size reaction vessel. Duplicating the exact frequencies of platinum into a big industrial reaction vessel will be a slow process because the energy will be. quickly absorbed at the edges of the container.
\Vhat we really need to quickly get energy into a big industrial sized container is a lower frequency energy, that \Vill penetrate farther into the vat of chemicals. We can do this quite neatly by copying nature. Remember, the spectra of atoms and molecules are broadly classified into three (3) different groups - electronic, vibrational, and rotational. The electronic spectra of atoms and small molecules are said to result from transitions of electrons from one energy level to another. and have the highest frequencies, occurring in the ultraviolet (UV), visible. and infrared (IR) regions of the EM spectrum. The vibrational spectra are said to result from stretching of bonds between individual atoms within molecules, and occur in the infra-red and microwave regions. Rotational spe,ctra occur in the microwave and radiowave regions of the EM spectrum, from rotation of molecules in space.
If we could use a microwave or radio\.vave frequency, we could spectrally catalyze a platinum-catalyzed reaction in large quantities. But platinum does not produce frequencies in the microwave or radiowave portions of the spectrum. So how can we catalyze a platinum-catalyzed reaction using microwaves? We simply copy the mechanism of action of platinum, and move it to the microwave part of the spectrum.
The mechanism is: energizing a reaction intermediate. The reaction intermediates are: atomic hydrogen and the hydroxy radical. Atomic hydrogen has a high frequency electronic spectrum. The hydroxy radical, on the other hand, is a small molecule, and has vibrational and rotational spectra as well as an electronic spectrum. Thus the hydroxy radical produces frequencies in the microwave part of the electromagnetic spectrum.
We copy the mechanism of action of platinum - namely resonating with a reaction intermediate. We resonate with the hydroxy radical. Instead of resonating with hydroxy in its electronic spectrum, as physical platinum does. we use one of hydroxy' s frequencies in the microwave part of the spectrum. Hydroxy has a microwave frequency at 11.-l GhzQ. Energizing a reaction
'I
\ I 1c·roh <.J\ ~· Sr,~·-·trn ,~·1 •_['\
system of hydrogen and oxygen gas with a spectral catalyst at 21.4 Ghz \vill
catalyze the fonnation of water. In this case we copied the mechanism of
action of the physical catalyst platinum, and moved the mechanism to a more
convenient portion of the electromagnetic spectrum.
Look at the second item on our list - harmonically energizing a reaction
intermediate. What if \Ve wanted to use a bank of lasers to catalyze our
hydrogen oxygen reaction. but the frequency range of our lasers was only
from 1500 to 2000 Thz. \Vhat then? Platinum does not produce frequencies
in that part of the E~1 spectrum. The nvo hydroxy frequencies that platinum
resonates \~·ith, 975 and 1060 Thz~ are outside that range. Likewise, the
hydrogen spectrum goes from 40 Thz up to 3236 Thz, but it does not have
any frequencies between 1500 and 2000 Thz (Figs. 8-10).
The ans\ver is simple. We copy the mechanism of action .of platinum
and adapt it to our available equipment. We use harmonics of the reaction
,,;;,,intermediates in the portion of the E\.1 spectrum available to us with our
11
' lasers. For the hydroxy radical, with frequencies of975 and 1060 Thz, the
first harmonics are 1950 and 2120 Thz, respectively. Thus. some of our
lasers can be tuned to 1950 Thz to resonate harmonically with the hydroxy
radical. The first harmonics of three different hydrogen frequencies also fall
within our desired range. The fundamental frequencies are 755, 770, and 781
Thz and the first harmonics are 1510, 1540, and 1562 Thz, respectively.
Thus, some of our lasers can be tuned to the first harmonics 1·5 I0, 1540, and
1562 Thz.
Depending on how many lasers we have, we can go to third or fourth
harmonics as well. The third harmonic of the hydrogen frequency 456 Thz
falls at 1824 Thz, nicely within our part of the spectrum. Similarly, the
fourth hannonic of the hydrogen frequency 314 Thz is 1570 Thz, again
within our desired frequency range. In summary, we see that once again, we
can duplicate a mechanism of action of a physical catalyst and move it to a
portion of the electromagnetic spectrum that is more convenient for us.
What about the third item on our list - energizing a reaction inter-
mediate at multiple upper energy levels, setting up an atomic scale laser
system? Think about our example above with the bank of lasers. Lets say
we have ten lasers. There are 4 first harmonics within our equipment
frequency range of 1500 to 2000 Thz. Should we set all ten lasers to these 4
hannonics only, or should \Ve set some of the lasers to third. fourth, and
higher harmonics?
A mechanism that physical platinum uses is to resonate with multiple
~ /:JfZJ/47-/<P-Y~
Page - . ) e r •
ruf ;(7f1hr
upper energy levels of the reaction intermediate. The more upper energy
levels, the better. This creates an atomic scale laser system with
amplification of the electromagnetic energies being exchanged between the
atoms of platinum and hydrogen. This amplification of energy catalyzes the
reaction at a much faster rate than it would ordinarily proceed. We can take
- advantage of this mechanism to catal.vze the reaction with our available
equipment.
- Rather than setting all ten lasers to the 4 first harmonics and energizing .....,
only 4 energy levels, we want to energize as many different energy levels as
possible. We do this by setting each of the ten lasers to a different frequency.
Even though the physical platinum is not present, the energizing of multiple
upper energy levels in the hydrogen will amplify the energies being
exchanged between the atoms, and the reaction system will fonn its' own
laser system between the hydrogen atoms. This will allow the reaction to
proceed at a much faster rate than it ordinarily would. Once again, we have
;i'!;~copied nature by duplicating one of her mechanisms of action.
,,~E
The preceding discussion on duplicating catalyst mechanisms of action
is far from an exhaustive review of the subject. There are many factors and
variables that affect both catalyst perfonnance, and chemical reactions in
general. We can learn many interesting things from modem chemistry about
the mechanisms of catalysts and chemical reactions. For instance, the same
catalyst, mixed with the same reactant, but exposed to different conditions
such as temperature or pressure, will produce different products. Consider
the following example':
--------- 1. Cyclohexene
> 300" C
Benzene + 2H2
Pd catalyst
2. Cyclohexene
< 300' C
-------- ---
..... Benzene + 2Cyclohexane
Pd catalyst
The same catalyst with the same reactant. produces quite different products - molecular hydrogen or cyclohexane - depending on the reaction temperature. If catalyst activity is merely a matter of the frequencies it
Page -3rflll3 '9-/q,L'frsl1/,f?r
produces. then how can this be? If a physical catalyst actually catalyzes a reaction by virtue of the electromagnetic spectral pattern it emits. then why \vould temperature affect catalyst activity?
The answer to this question again comes from advances in the field of spectroscopy. \.-1any factors are known to affect the direction and intensity with which a physical catalyst guides a reaction. Temperature is but one of these factors. Other factors include pressure. volume. surface area. solvents and support materials. contaminants. catalyst size and shape. reaction vessel size and shape, electric fields. magnetic fields. and acoustic fields. These factors all have one thing in common. They change the spectral frequency patterns of atoms and molecules. Some of these changes are so well studied that entire branches of spectroscopy have been designed around them. The next several sections will discuss each factor and its' influence on catalyst mechanisms of action, and chemical reactions in general.
Temperature Let's start with temperature. At very low temperatures, the spectral pattern of an atom or molecule has clean crisp peaks (Fig. 15.a.). As the temperature increases, the peaks begin to broaden, producing a bell curve type of spectral pattern (Fig. 15.b.). At even higher temperatures, the bell curve broadens even more, to include more and more frequencies on either side of the primary frequency (Fig. 15.c). This phenomenon is called "broadening". These spectral curves are very much like the resonance curves we discussed in the previous section. Spectroscopists use resonance curve terminology to describe spectral frequency curves for atoms and molecules (Fig. 16). The frequency at the top of the curve- f0 - is called the resonance frequency. There is a frequency (f2) above the resonance frequency and another (f1) below it, at which the energy or intensity is 50% of that for the resonant frequency f0• When we discussed resonance curves we used the ratio of:
to calculate the resonance quality. Q, for a resonance curve. Spectroscopists use the frequencies a little bit differently. The quantity (t~ - f1) is a measure
Page -35,,c-/~~1f,(,,
.-\mpl•nude .A.-
Frequenc;, ➔ a) Spectral pattern at lov, temperature.
Amplitude:
\
I /
j
\j
V
Frequency ➔
b) Spectral pattern at moderate temperature.
. ...
Amplitude..-
J
Frequency ➔
c) Spectral pattern at high temperature.
Figure 15. Spectral patterns at different temperatures. the effects of temperature on spectral emissions. a) Spectral pattern at lov,· temperatures \\ith crisp narrow peaks. b)Spectral p::mern at moderate temperature \\ ith broader peaks. cl Spectral pattern .lt high temperature \\ith mw.:h broadc-ning of pc-aks.
lJfJ/Ja_,/<72--t3/-
Page - 3 ~ •
. ,J(J '1/tt(rf
of how wide or narrow the spectral frequency curve is. Spectroscopists call
this quantity (t~ - f1) the ··line width". A spectrum with narrow curves has a small line width, while one with \\:ide curves has a lar.g....e line width.
Amplitude:
Line \\idth
I
f,
Frequency ➔
Figure 16. Spectral curve showing line width (f: - f1).
Temperature affects the line width of spectral curves. Line width can affect catalyst performance and chemical reactions. At low temperatures, the spectral curves of chemical species will be separate and distinct, with little transfer of resonant energy (Fig. 17.a). As the line widths of the chemical species get broader and broader, their spectral curves may start to overlap with matching frequencies (Fig. 17.b.). When the frequencies match at higher temperatures, resonant transfer of energy takes place and the reaction can proceed in a different direction than it otherwise would have at a lower temperature.
Besides affecting the line width of the spectral curves, temperature also can change the resonant frequency and the amplitude of the curves. For some chemical species the resonant frequency will shift as temperature changes. This can be seen in the infrared absorption spectra and blackbody radiation graphs in Figure 18. Atoms and molecules do not all shift their resonant frequencies by the same amount or in the same direction, at the same temperatures. This can affect catalyst performance. If a catalyst resonant frequency shifts more with increased temperature than the resonant frequency of its· target chemical. then resonance may be created where none pre\'iously existed. (Fig. 18.c.}
Amplitude:
j
_jl L II ______,,,
Frequency ➔
a) Separate and distinct spectral curves at lo\\ tetnperature.
Amplitude :
Frequency ➔
b) Overlapping spectral curves at higher temperature. allowing resonant energy transfer.
Figure 17. Effects of temperature on spectral curve line widths and resonant transfer ofenergy.
I::?
10
I
6 ),4
a) Lowering of resonant frequency (increasing wavelength) as temperature
increases in right hand set of curves.
Figure 18. Effects of temperature on resonant frequency. a. Influence of temperature on
the resolution of infrared absorption spectra'''
Page -3
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/\Jf f (1/r'(f, f
I
11 20-•1
I
I
,;;- I00 ~j-1
' 8
i I
c
I I
:i 80- -,
I
\
I
"' 6-.) -1
0
5
20
>... ll 10 4 (cm)
18.b. Spectral radiant emittance of a blackbody: (a) 800 K. (b) 1200 K. (c) 1600 K. (d) 1600 K {Wien). (e) 1600 K (Rayleigh). (t) 6000 K. (g) 10.000 K. The decrease of resonance wavelength. and hence increase of resonance frequency. is sho-v.n by the dashed curve. 11
A
Figure 18.c. At low temperature the catalyst (C) does not resonate with target chemical species (A). At high temperature. the catalyst's resonant frequency shifts and resonance exists between C and A.
The amplitude or intensity of a spectral line may be affected by temperature also9. For instance, linear and symmetric rotor molecules will increase intensity as the temperature is lowered. Conversely, rotational or vibrational spectra may decrease intensity as the temperature is lowered. These changes of spectral intensity can affect catalyst performance. Consider
the example where a low intensity spectral curve of a catalyst is resonant with a chemical target"s frequency. Only small amounts of energy can be transferred from the catalyst to the target chemical. Say that as the temperature increases, the amplitude of the catalyst's curve increases also. In
. -- this case the catalvst can transfer much larg;er amounts of energy to the ~
chemical target. If the chemical target is the intermediate chemical species for an alternative reaction route. the type and ratio of end products may be affected.
Look at our cyclohexene, palladium reaction again. At temperatures beloir 300 C the products are benzene and hydrogen gas. When the
temperature is above 300 C the products are benzene and cyclohexane.
Temperature is affecting the palladium and/or the rest of the reaction system (including reactants, intermediates, and products) is such a way that an alternative reaction pathv.,·ay leading to the formation of cyclohexane is favored above 300 C. This could be a result of increased line width, altered resonance frequencies, or changes in spectral curve intensities for any of the chemical species in the reaction system.
It is important to consider the spectral catalyst frequencies under the reaction conditions we want to duplicate. Say for instance that at temperatures above 300 C. the reaction system is unaffected but the palladium has an increased line width. lower resonant frequency, and increased intensity. Also say for instance that the wider line width and lower resonant frequency interact with an intermediate important for the formation of cyclohexane. If we wanted to spectrally catalyze the formation of cylcohexane at room temperature, we would need to use the wider, lower spectral catalyst frequency for palladium above 300° C.
Thus it can be important to understand the reaction system dynamics in designing and determining a spectral catalyst. Otherwise, one is reduced to using random, trial and error or feedback-type analyses which; although they \Vill eventually identify the spectral catalyst frequencies, will be very timeconsuming. The trial and error techniques for determining spectral catalysts also have the added drawback, that having once identified a frequency, one is left with no idea of what it means 12. If one wishes to modify the reaction, another trial and error analysis becomes necessary rather than a simple, quick calculation.
Pressure
Pressure and temperature are direct!) related to each other. Everyone . probably remembers the ideal gas law from high school chemistry:
PV = nRT,
where Pis pressure.Vis volume. n is the number of moles of gas. R is the gas constant, and Tis the absolute temperature (Celsius plus 273 - ). All things being equal. if temperature increases. so does pressure. Given this similarity between the effects of pressure and temperature in chemical systems. one might wonder if they have similar effects on spectral emission patterns. The answer is yes. Increased pressure causes broadening and other changes in spectral curves. just as increased temperature does (Fig. 19).
1ox10·• , - - - - - - - - - , - - - - - . . . - - - - , - - - - - - ,
PRESSURES:
o p=C8JmmHt; • p:OVmmHt;
Cv2pZ
~
CURVES: ( v·vo)Z T(2~4 p)Z
;:- 6x10-• 1------,....--.....-----.tt-t-+--+-1t----+------1
2c·
o
4,110-• 1------+---+-__,,...,-'--t--'rt----+------1
a.
§
0
~ 2x10-• 1-----,.51---=+--.:;.<---+--+-l'--"<c---+--~
23,700
23,750
23,800 23,850 23,900 Freque11ey, meqacyclft
23,950 24,000
Figure 19. Effect of pressure broadening on the NH3 3.3 absorption line<!.
Mathematical treatments of pressure broadening are generally grouped into either collision or statistical theories4• In collision theories. the
assumption is made that most of the time an atom or molecule is so far from
other atoms or molecules that their energy fields do not interact. Occassion-
ally, however, the atoms or molecules come so close that they collide. In this
case. the atom or molecule may undergo a change in wave phase function. or a
change to a different energy level. Collision theories treat the significant
radiation as occurring only \\ hen the atom or molecule is far from others. and is not involved in a collision. Because collision theories ignore spectral
frequencies during collisions. they fail to accurately predict chemical behavior
at more than a few atmospheres of pressure. \\ hen collisions are frequent.
P a g e ~,;G' ~ / ~ - 7 7 '
-
µfl 11-j'f/!1
Statistical theories, ho\vever, consider spectral frequencies before,
during, and after collisions. They are based on calculating the probablilities
that \iarious atoms and molecules are interacting with or perturbed by other
atoms or molecules. The drawback with statistical treatments of pressure
effects
is
that
thev-
do
not
do
a
.g,_, ood
..job
of accounting "-"
for
the
effects
of
molecular motion. In any event. neither collision or statistical theories
adequately predict the rich interpla) of frequencies and heterodynes that take
place as pressure is increased.
Experimental work has demonstrated that increased pressure can have
effects similar to those produced by increased temperature, with:
1) broadening of the spectral curve producing increased line width; and
2) shifting of the resonant frequency. t~.
Unlike temperature, however, pressure changes usually do not affect intensity
or energy amplitude (Fig. 20).
,
t
,_
Figure 20. Theoretical shape of pressure-broadened lines for three different pressures9. The intensity is unchanged. t.v=0.01 v0 is the lowest pressure and t.v=0.3v0 the highest pressure curve.
Pressure broadening differs from temperature broadening in one other
significant aspect. The curves produced by pressure broadening can be less
symmetric than the temperature affected curves. Consider the shape of the
three curves in the theoretical work above (Fig. 20). As the pressure
increases. the curves become less and less symmetrical. A tail extending into
the higher frequencies develops. This upper frequency extension is confinned
~t{;l-/(/4-ff
Page - 4 ~ •
NfI 11/Nftr
by experimental \\ ork (Fig. 21 ).
6x10·1r - - - - - - - - - - - - - - - - - .
\ 4x10·1
.!.E..
8 3X!(Y7 ~
Q
~ 2,c•Q"7
~
CL~er,l-:en 1a1
0
15.000
20,COO
25,0CC .lC.:00 )5,COO
v. meqoc1c .es
4C,CCO
45,000
a)
10
9
.. 8
'o -; 7
;-e
-~... 6
C 5
!? 0.4
~
.c,
4 3
.,,- ....,,,
~oretica1 _ _ ' , . . . , _ _ _ _ _ _ _ _ _ _ _ _ r
..
I
I I
I I I I
2
30 60 90 120 1~ 180 ZIO 240 270
b)
Figure ~ 1. Experimental confinnation of upper frequency tail produced at increased pressuresQ.
a)
Absorption
by
water
vapor
in air (10
g of H10
per cubic
meter);
b)
Absorption
in NH at 3
1 attn
pressure.
Pressure broadening effects on spectral curves are broadly grouped into two types: resonance or "Holtsmark" broadening, and "Lorentz" broadening13. Holtsmark broadening is secondary to collisions between atoms of the same element, and thus the collisions are considered to be symmetrical. Lorentz broadening results from collisions between atoms or molecules which are different. The collisions are asymmetric. and the resonant frequency,~), is often shifted to a lower frequency. This shift in resonant frequency is shown
t•n F.1g. -1 0. The changes in spectral curves and frequencies that accompany changes
in pressure can affect catalysts and chemical reactions. At low pressures, the spectral curves will be fairly narrow and crisp. and nearly symmetrical about the resonant frequency. As pressures increase. the curves may broaden. shift. and develop high frequency tails. At low pressures the spectral frequencies in
the reaction s.vstem mig._,ht be so different for the various atoms and molecules
that there is no resonant effect. At higher pressures, the combination of broadening, shifting and extension into high frequencies can produce overlapping between the spectral curves, with creation of resonance where none previously existed. The reaction system may proceed down one path or another. depending on the changes in spectral curves produced by the pressure changes. One reaction path may be resonant. and hence proceed at moderate pressure. while another reaction path may be resonant and predominate at ..higher pressures. As with temperature, it is important to consider the spectral ;:::Fatalyst frequencies and mechanisms under the reaction conditions we want
i:tfo duplicate.
Surface Area
.
Traditionally, the surface area of the catalyst is considered to be
;:::jmportant because the available surface area controls the number of available
/~binding sites. The more exposed binding sites, the more catalysis, or so the
,,.Jheory goes. In light of the spectral mechanism underlying the activity of
1
:;;'.iphysical catalysts, surface area may be important for another reason.
i",;
Many of the catalytically active frequencies produced by physical
catalysts are in the visible light and ultraviolet regions. These high
frequencies have very poor penetrance in large reaction vats full of chemicals.
The high frequency spectral emissions from a catalyst such as platinum or
palladium will not travel very far in a reaction system before they are
absorbed. Thus, an atom or molecule must be fairly close to a physical
catalyst to interact with its' electromagnetic radiation.
Surface area affects the probability that a particular chemical species,
will be close enough to the physical catalyst to interact with its electro-
magnetic spectral emission. With small surface area, few atoms or molecules
will be close enough to interact. .-\s surface area increases, so too does the
probability that more atoms or molecules \\ ill be within range. Thus, rather
than increasing: the available number of bindiniz sites. large surface area
'-
I ff/JJg/)-, /c/-;?y'
Page--+~
tJf f tlfrfrr
increases the volume of the reaction system exposed to the spectral catalyst frequencies.
Catalyst Size and Shape
In a related line of reasoning, catalyst size and shape are classically
thought to affect physical catalyst activity. Particle size selectivity of
reactions has been used to steer catalytic pathv;ays for several years 1-t_ As
with surface area, certain particle sizes are thought to stabilize a maximum of
active binding.... sites and thus maximize the reaction rate 14.
Catalyst size and surface area are often intertwined theoretically.
\laximum catalyst activity is said to require maximum surface area, and
maximum surface area obtains from bits of catalyst as small as possible1•
Extremely fine powders of small catalyst particles are not stable however.
They have a tendency to coalesce into larger particles, thereby reducing
surface tension and remaining thermodynamically stable. When this happens
during use of a catalyst it is called ·•sintering". Sintering is thoU:ght to reduce
the number of active binding sites by reducing the surface area.
In light of the spectral mechanism underlying the activity of physical
catalysts, catalyst size and shape may be important for other reasons. One is due to a phenomenon called ""self absorption" 13 • When a single atom or
molecule produces its' classical spectral pattern it radiates electromagnetic
energy which travels out from the atom or molecule into neighboring space
(Fig. 22.). As more and more atoms or molecules group together, radiation
from the center of the group of is absorbed by its' neighbors and never makes
it out into space. Depending on the size and shape of the group of atoms, self
absorption can cause a number of changes in the spectral emission pattern
(Fig. 23.). These changes include a shift in resonant frequency and self-
... hv . ·.·.·.~..· ~
Nff-tv•
•••
Figure 22. Radiation from a single atom n. radiation from a group of atoms.
reversal patterns.
a) Normal spectral cun e produced b) a single atom
b) Resonant frequency (t~i) shift from self absorption c) Self-reversal spectral pattern produced by self absorption in a groups of atoms
d) Self-re\'ersal spectral pattern produced b~ self absorption in a groups of atoms
Fillure 23. Efft:cts ,_1f sdf absorption on thee :spectral emission patterns of groups of atoms or
·(f/ffi·~~ / ~ f f mvl;;;'i..:ule:s. a) spectra! pattern ofa single atom: b) resonant frequency shift c&dl self--reversal. Page --l-6
-
;,.Jff 1~117
Catalyst size and shape are also important to spectral emission patterns
because of the antenna-type transmitter effects produced by many atoms and
molecules, particularly metals such as many of the catalysts. As with
antennas in general, the larger the metallic structure, the lower the frequency
with which it resonates. So too. the larger the size of the catalyst, the lower
the antenna-type frequencies it\\ ill produce.
The changes in spectral curves and frequencies that accompany changes
in catalyst size and shape can affect catalysts and chemical reactions. For
single atoms. such as in a gas phase, the spectral frequencies in the reaction
system might be so different for the various atoms and molecules that there is
no resonant effect. With larger groups of atoms, such as in a solid phase, the
combination of resonant frequency shifting and self-reversal can produce or
eliminate over-lapping benveen the spectral curves of chemical species, either
creating or destroying conditions of resonance, respectively. The reaction
system may proceed do\vn one path or another, depending on the changes in
spectral curves produced by the particle sizes. One reaction path may be
resonant, and hence proceed at moderate catalyst particle size, \vhile another
reaction path may be resonant and predominate at larger catalyst sizes. As
with other factors, it is important to consider the spectral catalyst frequencies
and mechanisms under the reaction conditions we want to duplicate.
The changes in spectral curves and frequencies that accompany changes
in catalyst size and shape are relevant for practical applications. Industrial
catalysts are manufactured in a range of sizes and shapes, depending on the design requirements of the process and the type of reactor used1. Catalyst activity is proportional to the surface area of the catalyst bed in the reactor1.
Surface area increases as the size of the catalyst particles decreases'. Seem-
ingly, the smaller the catalyst particles, the better for industrial applications.
This is not always the case, however. When a very fine bed of catalyst
particles is used, high pressures are required to force the reacting chemicals
across the catalyst bed. The chemicals go in the catalyst bed under high
pressure, and come out the other side at low pressure. This large difference
between entry and exit pressures is called a "pressure drop". A compromise is
often required bet\veen catalyst size, catalyst activity, and pressure drop
across the catalyst bed.
The use of spectral catalysts allows for much finer tuning of this
compromise. For instance. a large catalyst size can be used so that pressure
drops across the catalyst bed are minimized. At the same time, the high level
of cat1lYst activitY obtained with a smaller catalvst size can still be obtained.
• •
- ~/cJ-/t7-~
Page-➔~
0fJ 12/Mfrr
by augmenting the physical catalyst spectrally.
Sav., for instance that a 10 mm catal.v, st has 50% of the activitv., of a 5 mm catalyst. With a 5 mm catalyst, however. the pressure drop across the reactor is so great that the reaction cannot be economically performed. The
compromise in the factory has been to use nvice as much 10 mm catalyst, to
- obtain the same amount of activitv. as v.-ith the original amount of 5 mm
catalyst. \Ve fine tune the compromise: use the original amount of 1Omm catalyst and augment \Vith a spectral catalyst. Catalyst activity is doubled by the spectral catalyst, giving us the same degree of activity as with the 5 mm catalyst. The size of the catalyst is larger, retaining the favorable reactor vessel pressure conditions for us. \Ve can perform the reaction economically, using half as much catalyst as we did in the past.
Another way to approach the problem is to do away with the catalyst all together. \Ve simply put a fiberoptic sieve, \Vith very large pores, in a flowthrough reactor vessel. The pore size is so large that there is virtually no pressure drop across the sieve, compared to the drop accompanying the 5 mm or even the IO mm catalyst. The spectral catalyst is emitted through the fiberoptic sieve, catalyzing the reacting species as they flow by.
Industrial catalysts are also manufactured in a range of shapes, as well as sizes. Shapes include spheres, irregular granules, pellets, extrudate, and rings 1• Some shapes are more expensive to manufacture than others, while some shapes have superior properties (catalyst activity, strength, and less pressure drop) than others. While spheres are inexpensive to manufacture, packed beds of spheres produce high pressure drops and the spheres are not very strong. Rings, on the other hand, have superior strength and activity and produce very little pressure drop, but they are also very expensive to produce.
Spectral catalysts allow us greater flexibility in choosing catalyst shape. Instead of using a packed bed of inexpensive spheres, with the inevitable high pressure drop and resulting mechanical damage to the catalyst particles, we can use a single layer of spheres augmented with a spectral catalyst. Our catalyst is inexpensive, activity is maintained, and large pressure drops are not produced, thus preventing mechanical damage and extending the useful life of our spheres. Similarly, we can use far smaller numbers of catalyst rings, and obtain the same or greater catalyst activity by supplementing with a spectral catalyst. The process can proceed at a faster flow-through rate because the catalyst bed will be smaller.
The use of spectral catalysts to augment existing physical catalysts has the following ad\·antages:
- it allows use of less expensive shaped catalyst particles; - it allows use of fewer catalyst particles overall; - it allows use of stronger shapes of catalyst particles; - it allows use of catalyst particle shapes with better pressure drop characteristics. The use of spectral catalysts to replace existing physical catalysts has similar ad\ antages: - it eliminates the use and expense of catalyst particles altogether: - it allovvs use of spectral catalyst deliver) systems that are stronger; - it allows use of spectral catalyst deliver)· systems with superior pressure drop characteristics.
Solvents
Generally, the term solvent is applied to liquid mixtures for \vhich the
solvent is a liquid and the solute (reacting chemical species or catalyst) can be
a
gas,
liquid,
or
solid
5 1
.
(Although less common, solvents can also be gases or
solids, as well as liquids.) Solvents are grouped into three broad classes -
aqueous, organic, and nonaqueous. If an aqueous solvent is used, it means
that the solvent is water. Organic solvents include hydrocarbons such as
alcohols and ethers. Nonaqueous solvents are inorganic non-water substances.
Many catalyzed reactions take place in solvents.
Because solvents are themselves composed of atoms and molecules,
they can have pronounced effects on chemical reactions. Solvents are atoms
and molecules, and thus emit their own spectral frequencies. These solvent
frequencies undergo the same basic processes discussed earlier, including
heterodyning, resonance, and harmonics. Spectroscopists have known for
years that a solvent can dramatically affect the spectral frequencies produced
by its' solutes. Likewise, chemists have known for years that solvents can
affect catalyst activity. Unfortunately, the spectroscopists and chemists did
not associate these long studied changes in solute frequencies with changes in
catalyst activity. These changes in solute frequencies include spectral curve
broadening, changes of curve intensity, gradual or abrupt shifting of the
resonant frequency f0, and even abrupt rearrangement of resonant frequencies.
,o ,o
- - -f
a) Absorption spectra ofphthalic acid in hexane (dotted) and alcohol (solid).
2001
'60~
t I
,,~
1B
010--
I '
0 40~
0 oo-
<00
600
pJ
- -000
'
b) Absorption spectra of iodine in alcohol (A) and carbon tetrachloride (B).
I -------------------0:
-MO
c) Effect of mixtures of alcohol and benzene on the absorption frequency of phenylazophenol. Doned line is frequency.
Figure 2-t Effects of solvents on spectral patterns of chemical species solutes 1°.
Looking at Fig. ~4.a.. consider a reaction taking place in alcohol. in which the catalyst resonates with phthalic acid at l 250. the large solid curYe in the middle. If we change the solYent to hexane. the phthalic acid no longer
Page-5o~/4l-/~ff rJlt11/,(, 1
1250, it will no longer resonate \Vith the phthalic acid. The change in solvent
will make our catalv., st ineffective. Similarly, consider Fig. 24.b., \Vherein iodine produces a high intensity
curve at 580 when dissolved in carbon tetrachloride. In alcohol, the iodine
produces instead, a moderate intensity curve at l 050 and a lo\v intensity curve
at 850. Let's say \Ve are performing a reaction using a catalyst that resonates
directly with the iodine in carbon tetrachloride at 580. Assuming the catalyst
spectral pattern does not change, if we chang~ the solvent to alcohol, the
catalyst will no longer work. Its' frequency of 580 will no longer match and
resonate with the new iodine frequencies of 850 and l 050. Of course there is
always the possibility that the catalyst ,.vill change its spectral pattern with a
change of solvent. The catalyst could change in a similar manner to the
iodine. in which case it will continue to catalyze the reaction regardless of the
change in solvent. Conversely, the catalyst spectral pattern could change in a
direction opposite to the iodine ·s. The catalyst will again fail to catalyze our
original reaction. There is also the possibility that the change in the catalyst
could bring it into resonance with a different chemical species and help the
reaction proceed down an alternative reaction pathway.
Finally, consider the graph in Fig. 24.c. showing a variety of solvent
mixtures ranging from 100% benzene at the far left, to a 50:50 • of
benzene and alcohol in th~enter, to l 00% alcohol at the t right. ~olute
is phenylawpnenT~hl.ph~ylazophenol has a frequenc of 855""to~ 1st of
s, ,. the solVe,rix~s- 100% :mmliol aiid li:!r 50:50 be ene:alc I the
freqtfency •
or . benzene:alcohol the frequency is Stl I 855. A~65
99.5:0.5 benzene:a ol however, the frequency abruptly changes to 888. A
catalys:~~w--in 100% benzene by resonating with the phenylazophenol at
~(;5 8&0, will lose its activity is there is even a slight amount of alcohol in the
solvent. Once again, it is important to consider the spectral catalyst
frequencies and mechanisms under the reaction conditions we want to
duplicate.
Support Materials
Catalysts can be either unsupported or supported. An unsupported
catalyst is a formulation of the pure catalyst, \\·ith no other molecules present.
Cnsupported catalysts are rarely used industrially because they generally have
IO\\ surface area and hence lo\\ actiYit)-. The low surface area results from
sinterin2. or coalesence of small molecules of the catalvst into larger
-
0 - ~ Paee -
-5~
/c;/-::fP' c-Jtr tt(, h1
molecules. in a process which reduces surface tension of the particles. An
example of an unsupported catalyst is platinum alloy gauze, which is used for the selective oxidation of ammonia to nitric oxide. 1 Another example is small
silver granules, used to catalyze the reaction of methanol with air, to form formaldehyde. 1 When the use of unsupported catalysts is possible, their
- advantages include straig--htfonvard fabrication and eas.v installation in
industrial processes.
A supported catalyst is a formulation of the catalyst with other
molecules. the other molecules acting as a supporting skeleton for the catalyst.
Traditionally. the support molecules are thought to be inert, providing a
simple physical scaffolding for the catalyst molecules. Thus. one of the
functions of the support material is to give the catalyst shape and mechanical
strength. The support material is also said to reduce sintering rates. 1 If the
support is as finely divided as the catalyst, the support will act as a ··spacer"
between the catalyst particles. and hence prevent sintering. An alternative
theory holds that an interaction takes place bet\veen the catalyst and support, thereby preventing sintering. 1 This theory is supported by the many
observations that catalyst activity is altered by changes in support material
structure and composition.
Supported catalysts are generally made by one of three methods:
impregnation, precipitation, and crystallization. Impregnation techniques use
preformed support materials, which are then exposed to a solution containing
the catalyst or its precursors. The catalyst or precursors diffuse into the pores
of the support. Heating or another conversion process drives off the solvent
and transforms the catalyst or precursors into the final catalyst. The most
common support materials for impregnation are refractory oxides such as
aluminas and aluminium hydrous oxides. These support materials have found
their greatest use for catalysts that must operate under extreme conditions such as steam reforming1, because they have great mechanical strength.
Precipitation techniques use concentrated solutions of catalyst salts (usually metal salts). 1 The salt solutions are rapidly mixed and then allowed to
precipitate in a finely divided form. The precipitate is then prepared using a
variety of processes including washing, filtering, drying, heating, and
pelleting. Often a graphite lubricant is added. Precipitated catalysts have
high catalytic activity secondary to high surface area~ but they are generally
not as strong as impregnated catalysts.
Crystallization techniques produce support materials called zeolites.
The structure of these crystallized catalyst zeolites is based on SiO➔ and AlO➔
-.,/;yf//fg - / t p - ~
Page • ) ~ ,
/ / r,J/ f
r 1;;.,6,
.tetrahedral units 1 ( Fig. 25).
0
0
~/
.\l
/~
0
0
0
0
~/
Si
/~
0
0
Figure 25 - Tetrahedral units of silicon and alumina
These units link in different combinations to form structural families, \Vhich include rings, chains, and complex polyhedra. For instance, the SiO4 and AIOi tetrahedral units can form truncated octahedron structures, \vhich form the building blocks for A, X, and Y zeolites (Fig. 26).
O Oxygen • Aluminum or s11tcon
a) Truncated octahedron structure with lines representing oxygen atoms and comers are Al or Si atomst6
b) Zeolite ...\ - Truncated octahedrons joined by oxygen bridges between square faces Figure 26 - Zeolite structures using silicon and aluminum tetrahc!dral units as building blocks. 1
c) Zeolites X and Y - Truncated octahedrons joined by ox1gen bridges betv.een hexagonal faces
Figure .26 - Zeolite stmctures using silicon and aluminum tetrahedral units as buildin2 blocks.: a )Truncated octahedron 'Structure \\ ith Iines representing oxygen atoms and corners a';e AI or Si atoms: b) Zeolite A - Tmncated octahedrons joined by oxygen bridges between square faces: c) Zeolites X and Y - Truncated octahedronsjoined by oxygen bridges between hexagonal faces.
The crystalline structure of zeolites gives them a well defined pore size and structure. This differs from the varying pore sizes found in impregnated or precipitated support materials. Zeolite crystals are made by mixing solutions of silicates and aluminates and the catalyst. Crystallization is generally induced by heating. The structure of the resulting zeolite depends on the silicon/aluminum ·ratio, their concentration, the presence of added catalyst, the temperature, and even the size of the reaction vessels used. 1 Zeolites generally have greater specificity than other catalyst support materials - ie. they do not just speed up the reaction. They also steer the reaction towards a particular reaction path.
Support materials can affect the activity of a catalyst. Traditionally these effects have been attributed to geometric factors. There are undoubtedly spectral factors as well. It has been well established that solvents affect the spectral patterns produced by their solutes. Solvents can be liquids, solids, or gases. Support materials are nothing more than solid solvents for catalysts. As such, support materials will affect the spectral patterns produced by their solute catalysts.
Consider a glass of Cool-Aid. The liquid water is the solvent. The solutes are sugar, flavoring, and coloring. Now imagine freezing an ice cube of the Cool-Aid. The water is still the solvent, but it is a solid now, instead of a fluid. The solid water solvent still contains the same solutes of sugar,
- flavoring. and colorinQ:. ._ Just as dissolved sugar can be placed into a solid phase solvent.
catalysts are placed into support materials that are solid phase solvents. These support material solid solvents have the same spectral effects on catalysts that liquid solvents have. Support materials can change spectral frequencies of their catalyst solutes by causing spectral curve broadening, changes of curve intensity, gradual or abrupt shifting of the resonant frequency f0, and even abrupt rearrangement of resonant frequencies.
It is no surprise then that changes in support materials can have dramatic effects on catalyst acti\·ity. The support materials affect the spectral frequencies produced by the catalysts. The changes in catalyst spectral frequencies produce varying effects on chemical reactions and catalyst activity, including accelerating the rate of reaction and also guiding the reaction on a particular reaction path.
Poisoning
Poisoning of catalysts occurs when the catalyst activity is reduced by
adding a small
amount
of
another
chemical
species
1 •
Traditionally,
poisoning
is attributed to chemicals with available electrons, and to adsorption of the
poison onto the catalyst surface where it physically blocks reaction sites.
Neither of these theories satisfactorily explains poisoning however.
Consider the case of nickel hydrogenation catalysts1. They are
completely deactivated if only 0.1 % sulphur compounds by weight are
adsorbed onto them. Could 0.1 % sulphur really contribute so many electrons
as to inactivate the nickel catalyst? Could 0.1 % sulphur really occupy so
many reaction sites that it completely deactivates the catalyst? Neither
explanation is satisfying.
Poisoning phenomena can be more logically understood in terms of
spectral catalysts. Remember the example in the solvent section using a
benzene solvent and phenylazophenol as the solute? In pure benzene the
phenylazophenol has a spectral frequency of 880. The addition ofjust a few
drops of alcohol (0.5%) abruptly changes the phenylazophenol frequency to
855. If we were counting on the phenylazophenol to resonate at 880, we
would say that the alchohol had poisoned it. The addition of small quantities
of other chemical species can change the resonant frequencies (f0) of catalysts and reacting chemicals. The addition of another chemical species can act as a
poison to take the catalyst and reacting species out of resonance.
Besides changing resonant frequencies of chemical species. adding
small amounts of other chemicals can also affect the spectral intensities of the
P
a -
~
e~ - 5 5 ~ / 4
;
?-
/cf
'
--
?
;Y
tJf I
11.,ftr
catalyst and other atoms and molecules in the reaction system, either
increasing or decreasing them. Consider cadmium and zinc mixed in an
alumina-silica precipitate 10 (Fig. 27). A nonnal ratio between the cadmium
3252.5 line and the zinc 3345.0 line was determined. Addition of sodium,
potassium. lead. and magnesium had no effect on the Cd/Zn intensity ratio.
Addition of copper reduced the relative intensity of the zinc line and increased
the cadmium intensitY. Converselv. addition of bismuth increased the relative
*
intensity of the zinc line \vhile decreasing cadmium.
Zn/cd (s,)
J ' " 81 or C11 2.5
(cu)
5.0
75
Figure 27 - [nt1uence of copper and bismuth on the zinc/cadmium line ratio 1°.
Also, consider the effect of small amounts of magnesium on a copper aluminum mixture 10 (Fig. 28). Magnesium, 0.6%, causes marked reductions in line intensity for copper and for aluminum. At 1.4% magnesium, spectral intensities for both copper and aluminum are reduced by about a third. If the copper frequency is important for catalyzing a reaction, adding this small amount of magnesium would dramatically reduce the catalyst activity. We would say the copper catalyst had been poisoned by the magnesium.
_ , , R - , - - - - - - - - - - - - - - ,
... .... ,o------,,,,o=---.o-=--~60--,,,ao,---,oo==-----,-,:-,2c=,,-,-.,-,,.40
Figure 28 - Influence of magnesium on the copper aluminum intensit) ratio'".
Page-)-6-~
~
d
-
-
/
'
¢
'
. -1
~ (LI
(Vf J !r'l/i1
In summary, poisoning effects on catalysts are due .to spectral changes. Adding a small amount of another chemical species to a catalyst and reaction system can change the resonance frequencies or the spectral intensities of one or more chemical species. The catalyst might remain the same, while a crucial intermediate is changed. Likewise, the catalyst might change, while the intermediate stays the same. They might both change, or they might both stay the same and be oblivious to the added species.
Promoters
Just as adding a small amount of another chemical species to a catalyst
and reaction system can poison the activity of the catalyst, the opposite can
also
happen
1 •
When an added species enhances the activity of a catalyst, it is
called a promoter. For instance, adding a few percent calcium and potassium
oxide to iron-alumina compounds promotes activity of the iron catalyst for
ammonia synthesis. Promoters act by all the mechanisms discussed in
Solvents, Support Materials, and Poisoning. Not surprisingly, some
support materials actually are promoters. Promoters enhance catalysts and
specific reactions by changing spectral frequencies and intensities. While a
catalyst poison takes the reacting species out of resonance, the promoter
brings them into resonance. Likewise, instead of reducing the spectral
intensity of crucial frequencies, the promoter increases the crucial intensities.
If we wanted phenylazophenol to react at 855 in a benzene solvent, we
would add alcohol and call it a promoter. If we wanted the phenylazophenol
to react at 880, we would consider the alcohol a poison. Thus understood, the
differences between poisons and promoters are a matter of perspective, and
depend on which reaction paths and products we want. They both act by the
same underlying spectral mechanisms.
Concentration
Concentrations of chemical species are known to affect reaction rates and dynamics. Concentration affects catalyst activity. These effects are explained by the probabilities that various chemical species will collide with each other. At high concentrations of a particular species, there are a lot of individual atoms or molecules. The more atoms or molecules, the more likely
Page-57-~/4?--~ f f ·
~'
1l)l! 11/rrf1r
- - thev- are to collide \Vith something: else. This statistical treatment mav not
explain the entire situation. Take a look at Figure 29., ·with various concentrations of N-methyl urethane in a carbon tetrachloride solution. At low concentrations the spectral lines have low intensity. As the concentration is increased, the intensities of the spectral curves increase also. At 0.0 l molaritv the spectral curve at 3460 cm· 1 is the only prominent frequency. At 0.15 • molarity, the curves at 3370 and 3300 cm· 1 are also prominent.
Figure 29. Concentration effects on the v (N-H) frequencies of N•methyl urethane in carbon tetrachloride solutions. 17 A) 0.01 M: b) 0.03 M: c) 0.06 M; d) 0.10 M; e) 0.15 M.
As the concentration of a chemical species is changed, the spectral character of that species in the reaction mixture changes also. Suppose that 3300 and 3370 cm· 1 are important frequencies for a desired reaction path. At low concentrations, we will not see our desired reaction. If we increase the concentrations however (and hence the intensities of the relevant frequencies) the reaction will proceed down the desired path.
Fine Structure Frequencies In the Background section we discussed spectroscopy, that field of
science concerned with measuring the frequencies of energy and matter. Three broad classes of atomic and molecular spectra were reviewed. Electronic spectra, which are from electron transitions, have frequencies in the ultraviolet (UV), visible. and infrared (IR), and occur in atoms and molecules. Vibra-
tional spectra are from bond stretching bet\veen individual atoms within molecules, are in the IR, and occur only in molecules. Rotational spectra are from rotation of molecules in space. have micro\vave or radiowave frequencies, and occur only in molecules. This is the standard set of spectra found in any general book on spectroscopy.
This is also an over-simplification. The truth of the matter is sli2._:htlv.
more complicated, but much more interesting. There are actually two other sets of spectra - the fine structure spectra and the hyperfine structure spectra. The: occur in atoms and molecules, and extend from the infrared down to the low radio regions. These spectra are often mentioned in chemistry and spectroscopy books as an aside, because chemists tend to focus more on the traditional types of spectroscopy (electronic, vibrational, and rotational).
The fine and hyperfine spectra are found more often in publications by physicists and radio astronomers. For instance, cosmologists map the locations of interstellar clouds of hydrogen, and collect data regarding the origins of the universe by detecting signals from outerspace at 1.420 GHz, which is a hyperfine splitting frequency for hydrogen. Most of the large databases about the microwave and radio frequencies of molecules and atoms have been developed by astronomers and physicists, rather than by chemists. The microwave spectroscopy book cited in this paper was written by two physicists, not chemists. Because of this gap between chemists and physicists, use of the fine and hyperfine spectra in chemistry has been neglected by many.
Take another look at the frequency diagrams for hydrogen (Fig. 8 & 9) in the Background section. The Balmer series, frequency curve II, starts out with a frequency of 456 THz (Fig 30.a). Let's suppose we can look at this individual frequency in greater detail, with a spectral magnifying glass of sorts. We would find that instead of there being just one crisp narrow curve at 456 THz, there are really 7 different curves, very close together, that make up our curve at 456 THz. Figure 30.b. shows the emission spectrum for the 456 THz curve in hydrogen.6 A high resolution laser saturation spectrum gives us even more detail, like a spectral microscope, as shown in Figure 30.c.6 The se\ en different curves positioned very close together, which we see only when we look at the spectrum with very fine resolution, are fine structure curves or frequencies.
456
I
I
!
Relative
Intensity
616
690 731 755 770
'-
400 450 500 550 600 650 700 750 800 850 Frequency (THz) ➔
a) Balmer series II for hydrogen. frequency on X axis and relative intensitv on Y axis.
Emission spedl'\Jm r .. soK
b) Emission spectrum for the 456 THz frequency of hydrogen.
High resolution spectrum
-0.2 0 0.2 0.4 an· 1
c) High resolution laser saturation spectrum for the 456 THz frequency of hydrogen.
Figure 30. Fine structure spectra for the 456 THz_ frequency from hydrogen.6 Spectra taken at 70
K to reduce broadening of the lines. a) Portion of hydrogen electronic spectrum. b) Positions of
the seven underlying fine structure components are indicated with bars. c) The strong line is 15.233.0702 cm·: (456 THz) and the horizontal scale is relative to that wavenumber:s
18These frequencies differ slight!:, from the frequencies in the ,1sT database. The frequencies ii;:ed in
!his fozure J.re from·· ~1"111,, So..:crra •• b\ TP Sofile\. rather than the ~IS
-
,
Page -60-
abase.
/rJ ~/cf- PY
,v(I I flf.,~ 1
The hydrogen 456 THz frequency is composed of seven different fine structure frequencies. A group of several frequencies very close together like this is called a multiplet. Although there are seven different fine structure frequencies. they are all grouped around t\vo major frequencies. These are the two tall. high intensity curves seen in Fig. 30.b. These two high intensity curves are also seen in Fig. 30.c. at zero cm· 1(-+56.676 THz), and at relative wavenumber 0.34 cm· 1 ( 456.686 THz). \\'hen what appears to be a single frequency is composed predominantly of two slightly different frequencies, the t\vo frequencies are called a doublet, and the frequency is said to be split. The difference or split between the two predominant frequencies in the hydrogen 456 THz doublet is 0.34 cm·' wavenumbers, or l 0.2 GHz (0.0102 THz). This frequency, I0.2 GHz, is called the fine splitting frequency for hydrogen's 456 THz frequency.
Thus the individual frequencies seen in ordinary electronic spectra are composed of two or more distinct frequencies spaced very close together. The distinct frequencies spaced very close together are called fine structure frequencies. The difference, benveen two fine structure frequencies that are split apart by a very slight amount, is a fine splitting frequency (Fig. 31 ). Now you may think this is starting to get rather far afield from spectral catalysts. In case you are wondering where this is all going, please note for future reference that the operative word here is "difference", and the difference between any two frequencies is a heterodyne.
Relative lntensity
,,,1;-·f-o --i,\
/
/
\
/
\
I
\
I
I
/
l
!
I
I
I
\
\
I
\
\
1-----1
' ,_
Fine Splitting Frequency (f1 - rj' - -
Frequency ➔
Figur~ J l. Fin~ structure. Dotted lin~ (--- l is ekctronic spectrum frequency. f : solid lines, _ )
;J-_ ~re tine structure frequeni.:ies. f1 and f:. The difference (heterod:ne) between the fine structure
frequencies 1( - f l is the tine splitting freq:::: _ ;ffJJ/5 (
/cf--Pf
t T 61
e
,1) r !1rf7r,,
Almost all the hydrogen frequencies in Figs. 8 and 9 are doublets or multiplets. This means that almost all the hydrogen electronic spectrum frequencies have fine structure frequencies AND fine splitting frequencies (heterodynes ). Some of the fine splitting frequencies (heterodynes) for hydrogen are listed in Figure 32. These fine splitting heterodynes range from the microwave down into the upper reaches of the radio region.
FIGI;RE 32. - Fine Splitting Frequencies for Hydrogen
FreQJJenc~ {THz) 2466 456 2923 2923 3082 3082 3082
Orbital 2p
n2-3 3p 3d -+p 4d 4f
Wavenumber (~m- 1) Fine sglining Fr~Qu~nc~
0.365
10.87 GHz
0.34
10.20 GHz
0.108
3.23 GHz
0.036
1.06 GHz
0.046
1.38 GHz
0.015
448 MHZ
0.008
239 MHZ
There are more than 23 fine splitting frequencies (heterodynes) for just
the first (I) series in hydrogen. Lists of the fine splitting heterodynes can be found in the classic 1949 reference "Atomic Energy Levels" by Charlotte Moore 19. This seminal reference also lists 133 fine splitting heterodyned intervals for carbon, whose frequencies range from 14.1 THz (473.3 cm-1) down to 12.2 GHz (0.4 lcm·1). Oxygen has 287 fine splitting heterodynes listed, from 15.9 THz (532.5 cm·1) down to 3.88 GHz (0.13 cm-1). The 23 platinum fine splitting intervals detailed are from 23.3 THz (775.9 cm-1) to
8.62 THz in frequency (287.9 cm·').
Diagrammatically, the magnification and resolution of an electronic
frequency into several closely spaced fine frequencies is depicted in Figure
33. The electronic orbit is designated by the orbital number n = l, 2, 3, etc.
The fine structure frequency is designated as a. A quantum diagram for
° hydrogen fine structure is in Figure 34.2 Figure 35. shows the multiplet
splittings for the lowest energy levels of carbon, oxygen, and fluorine. 19
19 Atomic Energ~ Le\els..-\s Derived From the Anal)ses of Optical Spectra. Vols. 1-111. Charione E.
\h,ore Cir..:ularofthe~Jttonal BureauofStandards ➔ 6-.June 15. 19➔9.
~, I
- 5pe..:tra of -\t0ms and \lolecules. PF Bernath. O7'.ford L'ni,er •
Pag....e -6..,
n
➔---
3 _ __ ..,
---
_______ 2
➔ ---
3--2 ---
4 ---
3 ---
-------0
T;,., . . . . . .. . , ., Figure 33. Diagram of atomic electron levels (n) and fine structure frequencies (a). ". 2
10 869.1 MHz
<: ... ---.---'sin
i>11,1-'s,1,1
1057.9 MHz
••. _ _...,.__ _ 2pl/,I
Lyma, a at 1215.67 A
n•l
'sin.· .-·· _£a.6 GHz 2s,,2
Figure 34. Fine structure of then= I and n =2 levels of the hydrogen atom. 19
«w cm' !-?;n
,~p_, Z26.S cm•-1_ _
43.5 ~ 2
16..4 ,_,.·1
30
wt•~-1
0 cm C Po
o em-'-0 -3P2
° 0 Cm_-1 .__...2..pl/2 F
Figure 35. The multiplet splittings for the lowest energ:: !'evels for Carbon. Oxygen. and Fluorine.
-1-3.5 cnf = 1.3 THz. 16.-1- cm··= 490 GHz. 226.5 cm·1 = 6.77 THz. 158.5 cm· 1 =4.74 THz. 404
cm 1.:.1 THz.
Page -63
Now that you know atoms have fine structure frequencies, which are
split apart by differences or intervals (heterodynes) called ·fine splitting fre-
quencies, you are probably beginning to wonder about molecules as well.
Molecules also have fine structure frequencies. The origin and derivation for
molecular fine structure and splitting is a little different from that for atoms,
but the graphical and practical results are quite similar. In atoms, the fine
structure frequencies are said to result from the interaction of the spinning
electron \Vith its· own magnetic field. Basicallv, this means the electron cloud
~
~
of a single atomic sphere, rotating and interacting with its' own magnetic
field, produces the atomic fine structure frequencies. In the literature, you
will find this referred to as ·"spin-orbit coupling·•. For molecules, the fine
structure frequencies are the actual rotational frequencies of the electronic or
vibrational frequencies. So the fine structure frequencies for atoms and
molecules both result from rotation. In the case of atoms, it is the atom
spinning and rotating around itself, much the way the earth rotates around its
axis. In the case of molecules, it is the molecule spinning and rotating head-
over-heels. like a candy bar tumbling through the air.
Take a look at Figure 36. This shows the infrared absorption spectrum
of the SF6 vibration band near 28.3 THz (10.6 µm wavelength, wavenumber
Figure 36. The vibration band ofSF6 at wavelength IO µm. 1
948 cm·1) of the SF6 molecule.2 The molecule is highly symmetrical and rotates like a top. The spectral tracing was obtained with a high resolution grating spectrometer. There is a broad band between 941 and 952 cm·' (28. l and 28.5 THz) with three sharp spectral curves at 946, 947, and 948 cm·1 (28.3, 28.32. and ~8.34 THz). Now what if we take a narrow slice of the broad band and look at it in more detail?
Figure 37.a. shows a narrow slice being taken from between 949 and 950 cm· 1, which is blown up to show more detail below and in 37.b. A tunable semiconductor diode laser was used to obtain the detail. There are many more spectral curves which appear when we look at the spectrum in finer detail. These curves are called the fine structure frequencies for this molecule.
3850 MHz
.. ......... ·• ·• ·•,....... ~ ....... co. ... -,....
a) Slice from vibration band of SF6.
Ill MIi '"29'
3850 MHZ
b) Fine structure frequencies sho\rn in detail.
Figure 37....\ narrow slice from the vibration band of SF~· blown up to sho,\ more detail. with the
tine structure frequencies.
Page -65-
/;7-/t:r-7?
µIf I ! 1/.rfn
-- . The total enern:v of an atom or molecule is the sum of its' electronic
vibrational. and rotational energies. The simple Planck equation discussed in
the Background section:
E = hf.
can be rewritten as follows:
where Eis the total energy, Ee the electronic energy, Ev the vibrational energy, and Er the rotational energy. Diagrammatically, this looks like Figure 37. for
molecules. The electronic energy,£"', involves a change in the orbit of one of
the electrons in the molecule. 10 It is designated by the orbital number n = O, 1,
J
V
n
3
2 I
3
4
3
;:
:
2
4 3 2
4 __ 3 __
2_ _
-----3
4 __
3_ _
2 __
-----2
Figure 38. Diagram of rL'tational (J ). \ ibrativnal (\"). and ele-:tr0nic (n Jener~ le\ ds for a molecule.
2, 3, etc. The vibrational energy, E._., is produced by a change in the vibration
rate benveen two atoms within the molecule 1°, and is designated by a
vibrational number v = l, 2, 3, etc. Lastly, the rotational energy, Er, is the
energy of rotation caused by the molecule rotating around its' center of masst0. The rotational energy is designated by the quantum number J = l, 2, 3, etc .. as detennined from angular momentum equations.
Thus. \.vhen we look at the vibrational frequencies of SF6 in more detail, we see the fine structure molecular frequencies. These fine structure frequencies are actually produced by the molecular rotations, J, as a subset of each vibrational frequency. Just as the rotational levels J are evenly separated in Figure 38. they are also evenly separated when plotted as frequencies.
This may by easier to understand by looking at some other frequency diagrams. Figure 39 shows the rotational spectrum for hydrogen chloride21 . In Fig. 39.a., the separate waves that look like teeth on a comb, are the individual rotational frequencies. The whole big wave (the whole comb) that goes from 20 to 500 cm· 1 is the entire vibrational frequency. At low resolution, this would look like a single frequency peaking at 20 cm •1 (598 GHz) (Fig. 39.b.). This is very similar to the way atomic frequencies such as 456 THz look like just one frequency at low resolution, but tum out to be several different frequencies at higher magnification.
500
380
260
140
20
a)
.:: 1 lnfra-rt!d Spt!Ctroscop:, and \.folecular Structure. \.I Da\leS. El· • r Publ. Co. I963.
/c7-/ct--?P7
NPS rz/t{,;7
500
380
260
140
20
bl
Figure 39. The rotational spectrum for hydrogen chloride shO\\."ing fine structure detail. a) Pure rotational absorption spectrum of gaseous hydrogen chloride recorded "'1ith an interferometer. b)
The same spectrum at low resolution.
In Figure 40, the rotational spectrum (fine structure) of hydrogen cyanide is shown.20 Note again the regular spacing of the rotational levels. (This spectral tracing is oriented the opposite of what we are used to. It uses transmission rather than emission on the horizontal Y axis, so our familiar intensity notation increases as you go down on the Y axis, rather than up.)
;,C
25
30
, I
v\ I
.2C
• 20
.... .- ..... -. .,,,,,.. -....... ....._
Figure -+0. The rotational spectrum for h:, drogen c: anide. ··r is the rotational level.
Page -68
1cJ~1(-ff/
0/f l!/tc,f.,f
Finally. for a veritable symphony of rotational frequencies, take a look
at Fig-ure 41, showing- a vibrational band for FCCF22. All of the fine sa\\1ooth
spikes are the fine structural frequencies, corresponding to the rotational frequencies. Note the regular spacing of the rotational frequencies. Also note the undulating pattern of the rotational frequency intensity, as well as the alternating pattern of the rotational frequency intensities.
27!JO cm l
27201
---- I
------
7' ] •Cl ,..
Ptel
I
i
~-
I
I
I
I
,I
'41
ctO
l11J
I I
C 91 I a10
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i
11 rfl
oS d
2702 cm 1
I ;!
I ii i:
,.,_ ' 1 j 'I
'
'
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270)
I ~3 I 0
11,r,
Figure 41." 1 The v, - v5 band of FCCF. ,·,. is vibrational level one. and v5 is vibrational level 5. The vibrational level frequencies heterodyne (add and subtract) just like all frequencies. The additive heterodyne of,.,. and v.- are depicted in the spectral band showing the frequency band at ··.-1 •• ri·: - ,·_.). B = i·. - ~v;.
-- \'ibrat10n-R0tat1ona! Spectros.:op~ and \ 1olecular D~ n:imics. Ed Papousek.. World Sci.. I QQ7
G,_,/c(-9f
(UI 1 r1.1tr4r
Consider the actual rotational frequencies (fine structure frequencies) for the ground state of carbon monoxide listed in Figure 42.
Figure 42. Rotational Frequencies and Derived Rotational Constant for CO in the Ground State23
J Transition
Frequency (\-fHZ)
Frequencv <GHz}
O➔ l
115,271.204
115
1 ➔2
230.537.974
230
2➔3
345,795.989
346
3 ➔4
461,040.811
461
4➔5
576,267.934
576
5➔6
691,-+ 72. 978
691
6➔7
806,651.719
807
B0 = 57,635.970 ~IHZ
Each of the rotational frequencies is regularly spaced approximately 115 GHz apart. Now the quantum theorists will explain this as being due to the fact that the rotational frequencies are related to Planck's constant and the moment of inertia (center of mass for the molecule) by the equation:
h
B - ---------81t2 I
where B is a rotational constant, his Planck's constant, and I is the moment of inertia for the molecule. From there they go to a frequency equation for the rotational levels that looks like this:
f= 2B(J +I)
where f is the frequency, B is the rotational constant, and J is the rotational level. Thus the rotational spectrum (fine structure spectrum) for a molecule turns out to be a harmonic series of lines with the frequencies all spaced or
split (heterodyned) by the same amount. The physicists call this amount ··2B". and they call ""B" the ··rotational constant". In charts and databases of
molecular frequencies, B is usually listed as a frequency such as MHZ. This
is graphically represented for the first four rotational frequencies in CO in Figure 43.
2B
2B
2B
------------I------------1------------------------I
--I----------I---------1-
I------------I-----------1
B
B
B
B
B
B
Relati\e Intensity
/
100 150 200 250 300 350 Frequency (GHz) ➔
450 500
Figure 43. Graphical representation of fine structure spectrum sho\\-ing the first four rotational
frequencies for CO in the groW1d state. The difference (heterod)ne) between the molecular fine
structure rotational frequencies is 2 X the rotational constant B (ie. f2 - f1 = 2B). 1n this case B =
57.6 GHz (57,635.970 MHZ).
Now this is interesting for several reasons. The rotational constant B listed in so many databases is equal to one half of the difference between
rotational frequencies for a molecule. That means that B is the first subharmonic frequency to the fundamental frequency - 2B - which is the
heterodyned difference between all the rotational frequencies. The rotational
constant B listed for carbon monoxide is 57.6 GHz (57,635.970 w-IZ). This
is basically half of the 115 GHz difference between the rotational frequencies. If we want to stimulate a molecule's rotational levels we can use 2B, which is
the fundamental first generation heterodyne, or we ~an use just B, which is the
first subharmonic of that heterodyne. This is interesting for another reason as well. If you talk to a spectro-
scopist or physicist, they will tell you that if you want to use microwaves, you
will be restricted to stimulating levels at or near the ground state of the
molecule (n = 0 in Figure 37.). They will say that as you progress upward in
, ~; j / / c f - ~ Fi~mre 38 to the higher electronic and vibrational levels, vou are goimz: to be
~
~
Page-71{y
1Uf1 IZ/-,f,1
necessarilv.
in
the
infra-red.
visible.
and
ultraviolet
regions. ~
The reason this is
so interesting is that it is not true.
Take a look at Figure 38 again. The rotational frequencies are evenly
spaced out no matter what electronic or vibrational level you look at. The
even spacing in this diagram was not done just to make it look pretty. The
rotational frequencies actually are evenly spaced out as you progress upwards
- - through all the higher" ibrational and electronic levels. Take a look at Figure ~
-+4. which lists the rotational frequencies for lithium fluoride (LiF) at several
different rotational AND vibrational levels.
Figure 44. Rotational Frequencies for Lithium Fluoride (LiF)2°
Vibrational level
Rotational Transition
Frequency (MHZ)
0
O➔ l
89,740.46
0
1 ➔2
179,470.35
0
2➔3
269,179.18
0
3➔4
358,856.19
0
4➔5
448,491.07
0
5➔6
538,072.65
1
O➔ l
I
1 ➔2
1
2➔3
1
3 ➔4
1
4➔5
88,319.18 176,627.91 264,915.79 353,172.23 441,386.83
2
O➔ l
2
2➔3
2
3➔4
2
4➔5
86,921.20 173,832.04 260,722.24 347,581.39
3
1 ➔2
3
2➔3
3
3 ➔4
171,082.27 256,597.84 342,082.66
The dit1erences between rotational frequencies. no matter what the
\·ibrational level. is roughh· 86.000 to 89,000 t\-1HZ 86-89 GHz). Bv usinQ'. a
--
;cJ/'/✓-*-
P a g e . 72
(:..)f1 !!(,r4 7
microvvave frequency bet\veen 86,000 MHZ and 89,000 MHZ, one can stimulate the molecule from the ground state levels, all the way up to its' highest levels.
Remember in the Background section where we talked about the experiment performed by Cirac and Zoller? They used a wire composed of metal atoms. The wire had a natural oscillatory frequency (NOF). The individual metal atoms also had unique oscillatory frequencies. The NOF of the atoms and the >iOF of the wire heterodyned by adding and subtracting, the way all frequencies heterodyne,
NOF:iwm - NOFv.ire = Subtracted Frequency.itom-v.ire-
\Vhen they stimulated an atom on the wire with the Subtracted Frequencyatoml\ire• it heterodyned (added) with the NOF\,ire to produce NOFatom, the natural oscillatory frequency of the atom,
Subtracted Frequencyawm-v.ire + NOF1,ire = NOFatom·
The rotational frequencies of molecules can be manipulated the same way. The first rotational level has a natural oscillatory frequency (NOF) of 89,740 !v1HZ. The second rotational level has a NOF of 179,470 ~1HZ.
NOFrotational 1➔2 - NOFrotat1onalo-+I = Subtracted Frequency rotational2-t·
179,470 MHZ - 89,740 MHZ -
89,730 MHZ.
The NOFs of the rotational frequencies heterodyne by adding and subtracting, the way all frequencies heterodyne. The two rotational frequencies heterodyne to produce a subtracted frequency. This subtracted frequency happens to be exactly twice as big as the derived rotational constant "B" listed in nuclear physics and spectroscopy manuals. When you stimulate the first rotational
frequency in the molecule with the Subtracted Frequency rotational 2.1, it will heterodyne (add) \Vith the NOFrotational o-+t (first rotational frequency) to produce NOFrotauonal I➔:?, the natural oscillatory frequency of the molecule's second rotational level.
Subtracted Frequency rotat10r.:ii 2-1 + NOFrotat1onai 0-tl = NOFrot:monal I ➔:?
89,730 MHZ
+ 89.740 MHZ = 179,470 ~1HZ
Since the rotational frequencies are evenly spaced harmonics. the subtracted frequency will also add with the second level NOF to produce the third level \;OF. It will add with the third level NOF to produce the fourth level NOF . .-\nd so on and so on. By using one single microwave frequency you will stimulate all the rotational levels in a vibratory band.
Now if you excite all the rotational levels for a vibrational frequency, you will excite the vibrational frequency also. And if you excite all the vibrational levels for an electronic level, you will excite the electronic level as well. Thus, one can drive up into the highest levels of the electronic and vibrational structure of the molecule using a single microwave frequency. That is why the spectroscopists are wrong in stating that the use of microwaves restricts you to the ground state of the molecule. If you are trying to resonate directly with an upper vibrational or electronic level you cannot use a microwave frequency. If, however~ you imitate a mechanism of action from the catalysts - namely resonating with target species indirectly through heterodynes, you can use a microwave frequency to energize an upper level vibrational or electronic state. \Vith an understanding of the simple processes of heterodyning it becomes readily apparent why microwave frequencies do not really limit one to the ground state levels of molecules.
Catalysts use this trick, of stimulating target species indirectly by zapping them with heterodyned frequencies (harmonics). Catalysts also stimulate the target species by direct resonance with the fundamental frequency of interest. Here the rotational frequencies give us a bonus. Take a look at the first frequency in Figure 42. The first rotational frequency for CO is 115 GHz. The heterodyned difference between rotational frequencies is also 115 GHz. The first rotational frequency and the heterodyned difference between frequencies are identical. All of the upper level rotational frequencies are harmonics of the first frequency. This relationship is not as apparent when one deals only with the rotational constant "B", but a frequency based analysis makes it easier to see.
Take a look at the first level rotational frequencies for LiF as well. It is
nearly identical to the heterod) ned difference bet\veen it and the second level rotational frequency. The rotational frequencies are sequential harmonics of the first rotational frequency.
Nov~ if you stimulate a molecule with a frequency equal to 2B. the heterodyned harmonic difference between rotational frequencies, you will kill two birds with one stone. You will resonate with all the upper rotational frequencies indirectly through heterodynes, and you will also resonate directly with the first rotational frequency.
There are a whole host of constants used in spectroscopy that relate in some \vay or another to the frequencies of atoms and molecules, just as the rotational constant --B'' relates to the harmonic spacing of rotational fine structure molecular frequencies. The alpha (a) rotation-vibration constant is a good example of this. The alpha rotation-vibration frequency constant is related to slight changes in the frequencies for the same rotational level. when the vibrational level changes. Take a look at the frequencies for the same rotational levels, but different vibrational levels of LiF in Figure 44. This has been reformatted in Figure 45. The frequencies are almost the same, but vary by a few percent as one moves between Yibrational levels. The rotational transition 0 ➔ l has frequency 89,740.46 ~1HZ at vibrational level 0. At vibrational level 1, the 0 ➔ l transition is 88,319.18 :\1HZ, and at vibrational level 2 the 0 ➔ 1 transition is 86,921.20 MHZ. These slight differences between the same J rotational level for different vibrational levels are related to harmonics of the alpha frequency constant.
Figure 45. Rotational and Vibrational Frequencies for LiF
Rotational Transition
O➔ l 1 ➔2 2➔3 3 ➔4 4➔5 5➔6
89,740.46 179,470.35 269,179.18 358,856.19 448,491.07 538,072.65
88,319.18 176,627.91 264,915.79 353,172.23 441,386.83
86,921.20 173,832.04 260,722.24 347,581.39
171,082.27 256,597.84 342,082.66
Vibrational
0
I
2
3
Level
k]-~/cf-9/f
/IJ(J I t/1 ft1
Consider the rotational and vibrational states for OCS shown in Figure
-1-6.~ This figure shows the same rotational level (J = 1 ➔ ·2) for different
vibrational states in the OCS molecule. For the ground vibrational (000)
level. J = l ➔ 2 transition; and the excited state ( l 00) J = 1 ➔ 2 transition, the
difference between the two frequencies is equal to 4 X alpha1 (4a 1). In another excited state. the frequency difference bet\veen the ground vibrational
(000) level. J = l ➔ 2 transition. and the center of the two /-type doublets 4 X
alpha2 (4a2). In a higher excited vibrational state, the frequency difference between (000) and (0t)0) is 8 X alpha2( 8a2). Thus it can be seen that the rotation-vibration constants "a" are actually harmonic molecular frequencies.
Stimulating a molecule with an a frequency or a harmonic of it will either
directly resonate \Vith or indirectly heterodyne harmonically with various
rotational-vibrational frequencies for the molecule.
13001 10011
12001 W!Ol 11001 ln:01 lOOOI 101:01 102'101
(03l0)
121101
111~1 (12°ol IOl~I 103101
IOI-at
Figure 46". Rotational transition J = l ➔ 2 for the triatomic molecule OCS. The vibrational state
is given by vibrational quantum numbers in brackets (v I v: v 3 ), V: having a superscript i/i. In case
I = l. a subscript l is applied to the lower-frequency component of the /-type doublet. and 2 to
the higher-frequency component. The two lines at (01 10) and (01 10) are an /-type doublet.
s~parated by q1..
Another interesting constant is the /-type doubling constant. This can
also be seen in Figure 45. Just as the atomic frequencies are sometime split
into doublets or multiplets, the rotational frequencies are also sometimes split
into doublets. The difference between them is call the /-type doubling
constant. These constants are usually smaller (lower frequency) than the a
constants. For OCS the a constants are 20.56 and 10.56 \1HZ, while the/-
type doubling constant is 6.3 ~-tHZ. These frequencies are all in the
radiow~n·e portion of the electro-magnetic spectrum.
1%!?) /cJ-/cf--9'~
Page - 7 ~
lJfJ rYr,[r,
\Veil after that lengthy (and hopefully not too boring) discourse on fine
structure frequencies of atoms and molecules, this seems like a good time to
come up for a breath of fresh air, and discuss just what all this has to do with
spectral catalysts and chemical reactions. \Ve shall begin by considering the
case of atomic fine structure frequencies and splitting frequencies. From there
we \Vill move on to applications of molecular fine structure frequencies.
By way of review, the electronic frequencies seen in the atomic spectra
are not neat crisp individual curves. If we look at them in sufficient detail, we
see that each curve is made up of several other curves spaced so closely
together that they just look like one curve or line on a conventional spectrum.
The 456 THz frequency for hydrogen is actually made up of 7 different but
closely spaced frequencies. These are the fine structure frequencies. The
amount that the closely spaced frequencies are split apart is called the fine
splitting frequency.
Energy is transferred by two fundamental frequency mechanisms. If the
frequencies are the same, then energy transfers by direct resonance. Energy
can also transfer indirectly by heterodyning, ie. the frequencies match after
having been added or subtracted with another frequency. The direct or
;, indirect resonant frequencies do not have to match exactly. If they are merely
close, a lot of energy will still transfer.
In our reaction combining hydrogen and oxygen to form water, we
learned that energizing the reaction intermediates of atomic hydrogen and the
hydroxy radical are crucial to sustaining the reaction. The catalyst platinum
energizes both reaction intermediates by directly and indirectly resonating
with them. Platinum also energizes the intermediates at multiple energy
levels, creating the conditions for energy amplification. Let's say we want to
copy platinum's mechanism of action by making use of atomic fine structure
frequencies.
If we directly resonate with the fine structure frequencies we will simply
resonate with the same frequencies we discussed earlier with only slight
variations between the frequencies (456.676 and 456.686 THz for example).
This is no different from what we did earlier and has no advantages to what
we already know.
If we indirectly resonate vvith the fine structure frequencies, howe\·er. it
is another story altogether. How do we indirectly resonate with the atomic
tine structure frequencies? By using the fine splittirnz frequencies which are
-~ lcJ~/¢:.-7f/
Page - 7 7 ~
(Vf!J fl/.,fr,
simply the differences or heterodynes betv.een the fine structure frequencies. Look at the hydrogen 456 THz fine structure and fine splitting frequencies for hydrogen (figures 30, 32, and 34).
456.686 THz - 456.676 THz = 0.0102 THz = 10.2 GHz
If we irradiate hydrogen atoms \.vith 10.2 GHz electromagnetic energy
(micro\vaves), \Ve \vill energize the 456 THz electronic spectrum frequency by
- resonatirnr with it indirectlv. The l 0.2 GHz will add to 456.676 THz to ~
produce the resonant frequency of 456.686 THz. The 10.2 GHz will also
subtract from the 456.686 THz to produce the resonant fr.equency of 456.676
THz. Thus zapping a hydrogen atom with l 0.2 GHz will energize its' overall
456 THz frequency.
If \Ve want to use a combination of mimicked catalyst mechanisms, we
can try the following: 1) resonate with the hydrogen atom frequencies
indirectly through heterodynes (fine splitting frequencies); and 2) resonate
with the hydrogen atom at multiple frequencies. We would do this by using a
combination of microwave frequencies either simultaneously, in sequence, or
in chirps or bursts. For instance we could use the individual microwave
frequencies of 10.87 GHz, 10.2 GHz, 3.23 GHz, 1.38 GHz, and 1.06 GHz in a
sequence. Ifwe wanted to use radiowave frequencies, we could use 239 and
448 MHZ in sequence. There are many fine splitting frequencies for
hydrogen not listed here, so depending on the frequency range of our
equipment, we can Tailor the chosen frequencies to the capabilities of our
equipment.
Another way to deliver multiple electromagnetic energy frequencies
would be to use a lower frequency as a carrier wave for a higher frequency.
This can be done for instance by producing 10.2 GHz EM energy in short
bursts, with the bursts coming at a rate of 239 MHZ. This can also be done by
continuously delivering 10.2 GHZ EM energy and by varying the amplitude at
a rate of 239 MHZ.
Thus by mimicking the mechanism of action of catalysts and by making
use of the atomic fine structure and splitting frequencies we can energize
upper levels of atoms using microwave and radiowave frequencies. By
knov,;ingly energizing particular atoms, we catalyze and guide the reactions to
desired end products. Depending on the circumstances, the option to use
lo\\"er frequencies may have many advantages. Lower frequencies have much
better penetrance into large reaction spaces and volumes, and may be better
-7[JJ,r Page
/42 7 0 ~
-/<f:__ff
,,J/J
/l(n
6t
suited to large scale industrial applications. Lower frequencies may be easier
to deliver \vith portable, compact equipment, as opposed to ·large. bulky
equipment for higher frequencies such as lasers. The choice of frequencies
may be for as simple a reason as avoiding interference from other sources of
E~1 energy. In any event. an understanding of the basic processes of hetero-
dyning and fine structure splitting frequencies confers far greater flexibility in
our design of spectral catalyst systems. than simply reproducing frequency for
frequency. the spectrum of a physical catalyst. And it allows us to make full
use of the entire range of frequencies in the electromagnetic spectrum.
Last but not least, \Ve will discuss applications of molecular fine
structure frequencies. By way of review, the electronic and vibrational
frequencies seen in the molecular spectra are not neat crisp individual curves.
If we look at them in sufficient detail, \Ve see that each curve is made up of
several other curves spaced so closely together that they just look like one
curve or line on a conventional spectrum. The closely spaced frequencies are
produced by rotational motion of the molecule and are called the fine structure
frequencies. The amount that the closely spaced frequencies are split apart is
a harmonic of the rotational constant --s". The amount by which various
frequencies for the same rotational level vary slightly is a harmonic of the a
rotation-vibration constant. When a rotational frequency occurs as a doublet,
they are split (heterodyned) by a frequency or harmonic called the /-type
doubling constant.
Now let's go back to our hydrogen/oxygen reaction in terms of the
molecular fine structure. We want to catalyze the reaction by duplicating the
catalyst's mechanism of action in the microwave region. If your equipment is
like mine and only goes up to 24 GHz, that does not give you a lot to work
with. We know that platinum energizes the reaction intermediates of atomic
hydrogen and the molecule hydroxy. The B frequency for hydroxy is 565.8
GHz. That means the actual heterodyned difference between the rotational
frequencies is 2B, or 1,131.6 GHz. My equipment will not go that high, or
even as high as just the B frequency.
Interestingly, the a constant for hydroxy is 21.4 GHz. That frequency is
within the range of my equipment. So you can fill a reaction flask with
hydrogen and oxygen gas (we actually did this experiment) and irradiate it
with 21.4 GHz. The gigahertz energy is a heterodyne of the rotational
frequencies for the same rotational level but different vibrational level. The
heterodyned frequency energizes the rotational frequencies. which energize
the \ ibrational frequencies. \vhich energize the electronic frequencies, which
/2?fFjG/ /cf--*
Page -7 9 ~
J(lJ /Zfoftt
catalyze the reaction.
Now what if my equipment could deliver 565.8 GHz, or even I, 131.6
GHz? We could irradiate the reaction flask with one of those frequencies. All
of the rotational levels in the molecule would be energ._ized, from the .g..,round state all the way up. This copies a catalyst mechanism of action in 2 ways.
The first \vay is by energizing the hydroxy radical and sustaining a crucial
reaction intermediate to catalyze the formation of \vater. The second mecha-
nism copied from the catalyst is to energize multiple levels in the molecule.
Because the rotational constant B relates to the rotational frequency hetero-
dynes at al/ levels in the molecule. using it also energizes all levels in the
molecule. This potentiates the establishment of an energy amplification
system such as occurs with the physical catalyst platinum.
If we are energizing a molecule with an /-type doubling constant, we
can use that the same way we would use a fine splitting frequency from an
atomic spectrum. The difference between the t\vo frequencies in a doublet is a
heterodyne, and zapping the doublet \vith its· heterodyne (splitting frequency)
energizes the basic frequency.
Now if we want to get fancy, \Ve can use combination frequencies and
such, as we discussed for atomic fine structure. For instance, we could put in
a constant central frequency of 1,131.6 GHz (the heterodyned difference
between rotational frequencies for hydroxy) with a vibrato varying around the
central frequency by± 21.4 GHz (the a constant harmonic for variations
between rotational frequencies.) We could use 1, 131.6 GHz EM energy in
short bursts, with the bursts coming at a rate of 21.4 GHz.
Since there is slight variation between rotational frequencies for the
same level, we can use that frequency range to construct bursts. Let's say that
the largest Bis 565.8 GHz, giving a rotational frequency heterodyne of
1,131.6 GHz. Suppose that the smallest B is 551.2 GHz giving a rotational
frequency heterodyne of 1, I02 GHz. We can transmit "chirps" starting as
1,100 GHz and increasing in frequency to 1,140 GHz. If we really want to
get fancy, we can set the transmitter to "chirp" at a rate of21.4 GHz.
In any event, there are many ways to make use of the atomic and
molecular fine structure frequencies, with their attendant heterodynes and
hannonics. An understandin.g... of catal.v, st mechanisms of action enables us to
move our spectral catalyst system from the high frequency ultraviolet and
- - visible li12:ht re2ions. down into the more mana2....eable microwave and
radiowave re.g.....ions.
At
the
ver.. ·
least.
it
gives
""-
us
a
wav.,
to
calculate
and
deter-
mine the effects of microwave and radiowave enern:ies on chemical reactions.
-8✓-P Page
/47--/(f-:/lfftG1
Hyperfine Frequencies
Hyperfine frequencies are just like the fine structure frequencies, only different. Fine structure frequencies can be seen by magnifying a portion of a standard frequency spectrum. Hyperfine frequencies can be seen by magnifying a portion of a fine structure spectrum. Fine structure frequencies occur at lower frequencies than the electronic spectra, primarily in the infrared and micro\vave regions of the electromagnetic spectrum. Hyperfine frequencies occur at even lower frequencies than the fine structure spectra. primarily in the microwave and radio wave regions of the electromagnetic spectrum. Fine structure frequencies are caused by the electron interacting with its· own magnetic field. Hyperfine frequencies are caused by the electron interacting with the nucleus.
Remember the SF6 molecule we looked at in the fine structure section? The rotation~vibration band and fine structure are shown again in Fig. 47.2
3850 MHZ
...,.,...._._........... .._._._.._
Figure 47. SF6 rotation-vibration band and fine structure frequencies.~
The fine structure frequencies are seen by magnifying a small section of
the standard vibrational band spectrum. In many respects. looking at fine
structure frequencies is like using a magnifying glass to look at a standard
spectrum. \Vhen we magnify what looks like a flat and uninteresting portion
~fd_,/cf-<ft'
Page -8 ~
cJfJ /'f.,f1t
of a standard vibrational frequency band. we see many lower frequency curves. These lower frequency curves are the fine structure curves.
Now what would we see if we took a small uninteresting portion of the fine structure spectrum, and magnified it the same way we magnified the regular spectrum? A small portion of the SF6 fine structure spectrum is magnified belo\v in Figure 48.2
000
-
!14 . .
, , 71 (Mlfl)
Figure 48. SF6 fine structu*re spectrum with a small portion from zero to 300 magnified.~
Once again, we see that when a small uninteresting portion of the spectrum is magnified, we see many curves of even lower frequency. This time we magnified the fine structure spectrum, instead of the regular vibrational spectrum. What we see is that there are even more curves of even lower frequency. What if we magnify these other lower frequency curves? Figure 492 shows a magnification, of the two curves marked with asterisks in Fig. 48.
What looks like a single crisp curve in Figure 48 turns out to be a series of several curves spaced very close together. These are the hyperfine frequency curves. Remember that when we looked at the 456 THz curve from the electronic spectrum for hydrogen, we discovered that instead of it being a single crisp curve. it was really made up of seven curves spaced very close together (fig. 30. )? \Ve see the same thing when we magnify a fine structure curve. It is really made up of several more curves spaced very close together.
;:;_,/cf-Pf'
(\Jf I !lf.,ft1
These other cun·es spaced even closer together are call the hyperfine frequencies.
Take another look at the spacing of the hyperfine frequencies. The curves are spaced very close together at somewhat regular intervals. The small amount that the hyperfine curves are split apart is called the hyperfine splitting frequency. The hyperfine splitting frequency is a heterodyne. The concept is identical to the idea of the fine splitting frequency. The difference bet\veen two curves that are split apart is called a splitting frequency. As always. the difference between two curves is a heterodyned frequency. So hyperfine splitting frequencies are all heterodynes of hyperfine frequencies.
0
2$
II.Hr
a)
.Jt~
~1~-1~
II.HI 0
b)
Figure ➔9. \1agnitication of two cunes from fine structure of SF.. showing hyperfine structure frequencies. "\"ote the regular spacing of the hyperfine structure cun·es. a) ~fagnification of cun·e
- - ~"'~(c;l-/q-9? m::irkeJ \\ ith a ~inl.!le asterisk (*I. bl :\1a!mification of curw mark with a double asterisk (* * l.
c)f I !tf.,ft-,
Because the hyperfine frequency curves result from a_ magnification of
the fine structure curves, they occur at only a fraction of the frequency seen in
the fine structure curves and are thus lower. We need to clarifv., here this idea of frequencies being larger or smaller, higher or lower. When a frequency is
large, it is said to be a high frequency. Conversely, a small frequency is low.
This perspective of frequencies comes mainly from the way we hear sounds.
A large frequency sound at 20,000 Hz has a high pitch. A small frequency
sound at only 200 Hz has a low pitch. The high frequency sound - 20,000 Hz
- is much larger numerically ( I00 X) than the low pitched sound at 200 Hz.
Because of the way we hear sounds, we call a large frequency number high,
and a small frequency number low.
Even though we do not hear electromagnetic waves, \Ve apply the same
sort ofjargon to the electromagnetic spectrum. An E~1 frequency of one
million hertz is high compared to an EM frequency of only one thousand
hertz. We call an EM frequency of one thousand hertz low. This terminology
has an impact on the way we discuss fine and hyperfine frequencies.
Consider the hydrogen atom for which there is an electronic spectrum
frequency of 2466 THz. When we magnify the 2466 THz curve to look at the
fine structure, we see that it is made of at least two different curves spaced
very close together. The two curves are just 0.01087 THz apart, hence the
splitting frequency for the 2466 THz curves is 0.01087 THz.. Because the
fine structure curves are spaced so close together, they are split apart by only a
fraction of a terahertz (10 12 hertz). Since 0.01087 THz is smaller than 2466
THz~ it is a lower frequency.
Ifwe move the decimal point over three places, 0.01087 THz (10 12
hertz) becomes 10.87 GHz (109 hertz). Gigahertz frequencies are lower
(smaller) than terahertz frequencies. We usually use an exponent with a number, such as I09 or 1012, so that we do not have long strings of zeroes with
our numbers.
Now getting back to spectral frequencies, if we magnify a regular
spectrum we get fine structure frequencies. The fine structure frequencies are
really just several curves, spaced very close together around the regular
spectrum frequency. If we magnify fine structure frequencies we get hyperfine
frequencies. The hyperfine frequencies are really just several more curves,
spaced very close together around the fine structure frequency. The closer
together the curves are. the smaller the distance or frequency separating them.
~ow the distance separating any nvo curves is a heterodyned frequency. So
the closer to2:ether anv t\VO curves are. the smaller is the heterodvned
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frequency between them. The distance ben"·een hyperfine frequencies - the amount that they are split apart - is the hyperfine splitting frequency. It is also called a constant or interval.
The electronic spectrum frequency of hydrogen is 2466 THz. The 2466 THz frequency is made up of fine structure curves spaced I0.87 GHz (0.01087 THz) apart. Thus the fine splitting frequency is l0.87 GHz. ~ow the fine structure cun es are made up of hyperfine curves. These hyperfine curves are spaced just 1420, 178, 59, 52, 23, 18. 7, 4.2, and 2.7 MHz (106 hertz) apart. Thus 1420. 178. 59, 52, 23, 18. 7, 4.2, and 2. 7 \JHz are all hyperfine splitting frequencies for hydrogen. The hyperfine frequencies are spaced even closer together than the fine structure frequencies, so the hyperfine splitting frequencies are smaller and lower that the fine splitting frequencies.
The hyperfine splitting frequencies are usually written as megahertz (MHz= l 06 hertz). yfost of the frequency numbers are smaller than a gigahertz and are much smaller than a terahertz.
Thus the hyperfine splitting frequencies are lower than the fine splitting frequencies. This means that rather than being in the infra-red and microwave regions, as the fine splitting frequencies are, they are in the microwave and radiowave regions. These lower frequencies are in the i\1Hz (I06 hertz) and Khz ( 103 hertz) regions of the electromagnetic spectrum. Several of the hyperfine splitting frequencies for hydrogen are shown below in Fig. 50.6
Hyi)8(fine spitting (MHz)
2.71
'
702
. ••
. • 421 52.83
I 1" I 17 55
Figure 50.() Hyperfine structure in then= .2 ton= 3 transition of hydrogen. The hyperfine
; 9 - / { ( - f f ;pliltting ,~1Hz1 are indicated Jt the right-hand side o ~
Page - 8 { y ,
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The hyperfine splitting frequency for hydrogen at 1420 MHz has played an important role in the development of science and astronomy. Microwave radiation due to transitions between the hyperfine components of atomic hydrogen in interstellar space9 was first detected in 1951. The radiation has a wavelength of around 21 cm. It penetrates interstellar space and even the earth's atmosphere rather easily. The movement of various objects in our galaxy, the \'lilky Way. has been assessed by examining this hyperfine radiation produced by interstellar hydrogen gas. For instance, hydrogen hyperfine frequency observations have shown that in certain directions throughout our galaxy, there are several strips of gas each moving systematically at velocities matching the arms of a rotating spiral nebula9. It is from this evidence that astronomers have concluded that our galaxy is formed in the shape of a giant two-armed spiral, similar in shape to the yinyang shape of oriental tradition.
Let's look at another example of hyperfine frequencies. In Fig. 51, the hyperfine frequencies for CH3I are shown.9 These frequencies are a magnification of the fine structure frequencies for the molecule. Since fine structure frequencies for molecules are actually the rotational frequencies, what we are really looking at here is the hyperfine splitting of rotational frequencies. In this particular figure, we are looking at the hyperfine splitting of just the J = l ➔ 2 rotational transition. The splitting between the two tallest curves is less than 100 Nffiz.
l
I I
I
I
I
I
I
,..
I
I
I
I
I
I
I
I
I
I
I
I
I I
I
I I
I I
I
I
I
I
I
I
I
I I
I I I I
I II
I I
I
I
I
11
II
I I
11
I I
'.I
I
I
I
I
I
I
I
I I
I
I
Figure 51." H~pertine structure in the J 1 ➔ :2 rotational transition of CH).
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Figure 529 shO\VS another example for the molecule CICN. This set of
hyperfine frequencies is from the J = 1 ➔ 2 transition of the ground
vibrational state. The scale for ··Spectrum under high resolution" shows a bar with the notation I me. This means that the bar represents l MHz. This particular reference uses me for megacycle for megahertz. Notice that the hyperfine frequencies are separated by just a few megahertz~ and in a few places by less than even one megahertz.
SIMCt•vm
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·•;;:d i :I ' ,,_, 'H ''• •"1 -~ 1~-"1 •"1 ,no '-1.• 'It '"t" .'. -------,
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Figure 52.9 - Hyperfine structure of the J = l ➔ 2 transition for CICN in the ground vibrational state. Experimental values are compared to theoretical patterns.
The energy-level diagram and spectrum of the J = ½ ➔ 3/2 rotational
transition for NO is shown in Figure 53.9 The scale of the "Observed spectrum" is in "Mc", which means it is megahertz (MHz).
In Fig. 549, the hyperfine frequencies for NH3 are shown. Notice that the frequencies are spaced so close together that the scale at the bottom is in kilohertz (Kc/sec). The hyperfine features of the lines were obtained using a beam spectrometer.
F ,,.-------,----~
\ ' - - - - - - r - - - , . . - - 3'? '----....,...---..-- ''2
J a lfz
\ \
\
J a 1!z
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I I
5/2
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3/z
11?
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312
Calcu, oted spectrum
Obser.ed soectrum
Figure 53.9 - Energy level diagram and hyperfine frequencies for the NO molecule.
0 Ke/sec-
1Gso 1ioo
Figure 5-+.4 - Hyperfine frequencies for ~H:.
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You may remember that the fine structure frequencies are sometimes split into doublets. The same thing happens with hyperfine frequencies. In a place where we would nonnally expect to find only a single hyperfine frequency curve, there are two curves instead - one on either side of the location where we expected to find the single hyperfine frequency. Hyperfine doubling is shown below in Figure 559. This hyperfine spectrum ic- i.lso from
~H3, this time the third and fourth (J = 3 and 4) rotational levels. I ne doubling can be seen most easily in the J = 3 curves. There are two sets of
short curves, a tall one, and then two more short sets. Each of the short sets of curves is generally located where we would nonnally expect to find just one curve. There are two curves instead, one on either side of the main_ curve location. Each set of curves is a hyperfine doublet.
J=4
rwi
WJ li WJ
Figure 55.9 - Hyperfine structure and doubling of the NH3 spectrum for rotaitonal levels J = 3 and
J = 4. The upper curves show experimental data, while the lower curves are derived from
theoretical calculations. Frequency increases from left to right in 60 KHz intervals.
There are different notations to indicate the source of the doubling such
as / - type doubling, K doubling, and A doubling, and they all have their own
constants or intervals. Without going into all the nuclear theory behind these various types of doublets, suffice it to say that the interval between any two hyperfine doublet curves is a heterodyne, and thus all of these doubling constants represent frequency hetero~ynes.
You may recal I that the fine structure frequencies were caused by the
electron interacting \vith its' own magnetic field. The general rule of thumb for hyperfine frequencies is that they are caused by the electron interacting
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with the magnetic field of the nucleus. It is actually a bit more complicated than that because other factors also contribute to hyperfine-structure, such as finite nuclear mass and electric charge distribution in the nucleus, variation of the electron potential from a coulomb potential when electrons are within the nuclear radius, isotropic polarization of the nucleus by electron fields, and nuclear quadropole moments. The predominant factor for the hyperfine frequencies of any particular spectrum. depends on whether the spectrum is for an atom or a molecule, and on the type and arrangement of the various atoms that make up the molecule. Entire books in theoretical physics are written on this very subject, complete with horribly long and complicated equations, so we won't go into all this in a spectral catalyst paper. V./e will simply use the general rule of thumb that fine structure is caused by the electron interacting with its' own magnetic field, \vhile the hyperfine frequencies are caused by the electron interacting with the nucleus's magnetic field.
Well, now that you know all about hyperfine frequencies, you are probably wondering just what this has to do with spectral catalysts and catalyzing reactions. Or perhaps you have a pretty good idea where this is all going because you noticed that heterodynes keep popping up all over whenever we talk about hyperfine frequencies.
A frequency in an atom or molecule can be stimulated directly or indirectly. Let's say we want to stimulate the 2466 Thz frequency of hydrogen for some reason. We could get an ultraviolet laser and irradiate the hydrogen with 2466 Thz electromagnetic radiation. This would stimulate the atom directly. Ifwe only had microwave equipment, we could use hydrogen's fine structure splitting frequency of l 0.87 Ghz. The gigahertz frequency would heterodyne (add or subtract) with the two closely spaced fine structure curves at 2466, and stimulate the 2466 Thz frequency band. This would stimulate the atom indirectly.
Now what if our equipment did not even go up that high? What if our
microwave only had a range from 0.5 to 4 Ghz? In this case, we could use the hyperfine splitting frequency for hydrogen at 1.42 Ghz. The 1.42 GHz frequency would heterodyne (add or subtract) with the two closely spaced hyperfine frequency curves at 2466, and stimulate the fine structure curves at the 2466 Thz frequency band. Stimulation of the fine structure curves would in turn lead to stimulation of the 2466 Thz band for the hydrogen atom.
If we had only radio equipment, and no micro\vaves technology we could use the hyperfine splitting frequencies for hydrogen in the radio wave
Page - 9 ~,b'.-;ef'~J I'/rr/r;
portion of the electromagnetic spectrum. We could set up a radio wave pattern \vith 2. 7 MHz, 4.2 MHz. 7 MHz, 18 MHz, 23 MHz. 52 MHz, and 59 \llHz. This would stimulate several different hyperfine frequencies for the 2466 Thz band of hydrogen. and it would stimulate them all at the same time. This \vould cause stimulation of the fine structure frequencies, which in turn would stimulate the 2466 THz electronic band in the hydrogen atom.
Depending on our equipment and design constraints we could use some of the delivery mode tricks we discussed in the fine structure section. For instance, one of the lower frequencies could be a carrier frequency for the upper frequencies. A continuous frequency of 52 MHz could be varied in amplitude at a rate of 2. 7 1\ttHz. Or a 59 MHz frequency could be pulsed at a rate of 4.2 MHz. There are all kinds of ways these frequencies can be delivered, including different wave shapes, durations, intensity shapes, duty cycles. etc.
The point is, that when we have identified a frequency that we wish to copy for spectral catalyst purposes, we can stimulate that frequency by moving to whichever portion of the electromagnetic spectrum best suits our equipment and design requirements.
As a small aside, the scientific community has long maintained a schizophrenic
perspective on the subject oflow.frequency electromagnetic waves interacting with
matter. When it comes to nuclear physics. they readiZv admit that a 2. 7 NIH=.frequency.
lvith a wavelength several meters long, can affect an atom no larger than 10-10 meters in
its' largest diameter. Ifthat matter happens to be in a biologic organism, however. they
steadfastZv maintain that there is no way for the 2. 7 MHz radiation to interact with the
organism. They protest that there is no possible mechanism ofaction for a wavelength
several meters long to interact lt.:ith a human just 2 meters long. This is because for
biologic organisms they consider onZv antenna type interactions, where the dimensions of
the structure (human height) must be equivalent to or larger than the wavelength ofthe
electromagnetic radiation.
Ifhydrogen in a spectroscopJ· chamber can be stimulated by 2. 7 MHz. then
hydrogen in a human can be stimulated b_v this.frequency as well. Once one understands
spectral catalysts and the heterodyning effects of fine and h_iper.fine splitting.frequencies
on atoms and molecules, one must admit this as another mechanism for the interaction of
electromagnetic radiation in biologic organisms.
Biologic scientists divide electromagnetic radiation into ionizing radiation (ultra-
i-iolet and X-rayJ and nonioni=ing radiation /visible light, infrared. microwave. and radio
lt'l1\'eJ..\lost believe that ioni=ing radiation can cause potentialzv damaging changes in
biologic organisms. and hence should be ai·oided. They also believe that nonioni=ing
radiation poses no Threat to biologic organisms. as long as high power intensities are
in-aided to prei-ent simple thermal injury_ frorn the passage of/arge amounts ofenergy.
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This ignorance has been further compounded b_v the fact that even those scientists ,,..,·ho DO believe that there are nonthermal effects from nonioni=ing radiation, haven't the slightest clue as to the mechanisms. The_v ha\'e no concept ofthe importance offrequency to chemical reactions, much less a concept ofhon· lower.frequency radiation can influence higher frequency biochemical events.
Thus the situation has evolved over the last 50 years wherein a minority of scientists consistentlyfind evidence for a nonthermal effect ofvisible light. infrared light. microlraves. or radio wares. The_v rare(,; bother to measure the frequencies ofthe electrogmagnetic radiation under study. because they don ·1 knolr that frequency is even important. Their critics assail their experimental and epidemiologic results as flukes and serrendipitous happenstance. because the_v cannot articulate a mechanism for their results.
As a consequence. the use ofelectromagnetic devices has proliferated. with no attention to the health effects ofthe radiation .frequencies being used. This has led to an odd mixture ofaffects.for some ofthe random~v used.frequencies confer a beneficial or protecti\'e effect on the biologic organism, while other.frequencies produce damaging effects. For the same frequency. one pmrer level may be beneficial. while the other power level may be damaging. Electromagnetic radiation per se is not badfor biologic organsims. but we need to be aware of.frequency-specific effects before broadcasting them around the world wi/(v-nil~v.
Electric Fields
In the presence of an electric field, spectral frequency lines of atoms and
molecules can be split, shifted, broadened, or changed in intensity. The effect
of an electric field on spectral lines is called the ··stark Effect", in honor of
its· discoverer, J. Stark. In l 913 Stark discovered that the Balmer series of
hydrogen (curve II) was split into several different components, while using a
high electric field in the midst of his hydrogen flame. In the intervening
,years, Stark's original observation has evolved into a separate branch of
spectroscopy, namely the study of atoms and of molecular structure by
measuring the changes in their spectral lines caused by an electric field.
In the preceding sections we learned that fine structure and hyperfine
frequencies along with their low frequency splitting or coupling constants
were caused by interactions inside the atom or molecule, between the electric
field of the electron and the magnetic field of the electron or nucleus. The
Stark effect is really quite similar, only instead of the electric field coming
from inside the atom, it comes from outside instead. The Stark effect is just
the interaction of an external electric field, from outside the atom or molecule,
with the electric and magnetic fields already inside the atom or molecule.
When examining the Stark effect of electric fields, one must consider
the effects on atoms, and the effects on molecules. One must also consider the
nature of the electric field, such as whether it is static or dynamic. A static
el~ctric field is produced by a direct current. A dynamic electric field is time
varying, and is produced by an alternating current. If the electric field is from
an alternating current, then one must also consider the frequency of the
alternating current compared to the frequencies of the atom or molecule.
In atoms, an external electric field perturbs the electron's charge
distribution. This disturbance of the electron's own electric field induces a
dipole moment in it (slightly lop-sided charge distribution). This lop-sided
electron dipole moment then interacts with the external electric field. In other
words, the external electric field first induces a dipole moment in the electron
field, and then interacts with the dipole. The end result is that the atomic
frequencies become split into several different frequencies. The amount the
frequencies are split apart depends on the strength of the electric field - the
stronger the electric field, the farther apart the splitting. This is shown in
Figure 566, which diagrams the Stark effect for potassium. Note that the
frequency splitting or separation of the frequencies (deviation from zero-fidd
waYenumber) Yaries with the square of the electric field strength (V/cm)2.
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4s 2S 1,2 - - - .....,____ M.11 :1,2
F1e1C1 ---1:,.-
(b) 2 P,.2
OO 1 2 3 4 5 6 7 8 9 XI 09 [Field (V1cm112
Figure 566 - The Stark effect for potassium. a) Schematic dependence of the 4s and Sp energy levels on the electric field. b) A graph plotting the deviation from zero-field positions of the
5p2Pl12.3. 2 +- 4s2Sl /2 transition wavenumbers against the square of the electric field.
\.\'hen the splitting varies with the square of the electric field strength, it is called a "second order" Stark effect, or a quadratic Stark effect. Most atoms have second order or quadratic Stark effects. The notable exception to this is hydrogen. In the hydrogen atom the splitting is directly proportional to the electric field strength. This is called a "first order" Stark effect, or a linear Stark effect. Thus hydrogen exhibits linear, first order Stark effects.24
The mechanism for the Stark effect in molecules is a little simpler than
it is in atoms. Most molecules already have an electric dipole moment (slightly uneven charge distribution). The external electric field simply interacts with the electric dipole moment already inside the molecule. The type of interaction - a first or second order Stark effect - is different for differently shaped molecules. For instance, most symmetric top molecules have first-order Stark effects.9 Asymmetric rotors usually have second-order Stark effects.9 Thus in molecules, as in atoms, the splitting or separation of the frequencies due to the external electric field, is proportional either to the electric field strength itself, or to the square of the electric field strength.
Pas..z... e -94-
i
i C 26,6301-----;;i,<~r----:~....,;_..-~==--i
.":: II 26,61 Of-7""'---~::::._---,.a::::.....------l
i
o 26.57 o~....;,10~.,.,20~.,.,,::;o-~------50~-ti0-:"J-.~ao
E'nu11'Cm 1
Figure 57~. - Frequency components of the J = O➔ I rotational transition for CH3Cl. as a function 1)f field strength. Frequency is given in megacycles (\1HZ) and electric field strength (esu'cm) is given as the square of the field. E~. in esu2, cm2.
An example of this is shown in Figure 579, which diagrams how the molecule CH3Cl responds to an external electric field. When the electric field is very small (less than 10), the primary effect is shifting of the three rotational frequencies to higher frequencies. As the field strength is increased (between IO and 20), the three rotational frequencies split into five different frequencies. With continued increases in the electric field strength, the now five frequencies continue to shift to ever higher and higher frequencies. Some of the intervals or differences between the five rotational frequencies remain the same regardless of the electric field strength, while other intervals become progressively larger and higher. Thus a heterodyned frequency might stimulate rotational levels at one electric field strength, but not at another.
Another molecular example is shown in Figure 589. This is a diagram of the Stark in effect in the OCS molecule which we examined in the Fine
Structure Frequencies section (Figure 46). When we looked at OCS earlier we were looking at the J = I➔2 transition for several different vibrational
levels, and at the slight differences in the same rotational frequency for different vibrational levels. The slight differences between the rotational frequencies were harmonics of the ct constant. In Figure 58, we are looking at just one frequency, from the several frequencies shown in Figure 46. That one frequency is a single frequency when there is no external electric field. \\'hen an electric field is added. however, the single rotational frequency splits
into t\\O. The stronger the electric field is. thj~~t~~,,~veen
Page -95(!!Jfl'.../
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the two frequencies. One of the new frequencies shifts up higher and higher. \vhile the other frequency shifts lower and lower. Because the difference between the nvo frequencies changes when the electric field strength changes, a heterodyned frequency might stimulate the rotational level at one electric field strength, but not at another.
6,--.----r------,--------.
5
4
~
2
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....e....•. 0
'ii
•1
·2
·3
-4
·5
-60
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2l
ll
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Figure 58~. • Theoretical and experimental measurements of Stark effects in the J = 1➔2 transition
of the molecule OCS. The unaltered absolute rotational frequency is plotted at zero, and the
frequency splitting and shifting is denoted as MHZ higher or lower than the original frequency.
Broadening and shifting of spectral lines occurs with the intermolecular Stark effect. The intermolecular Stark effect is produced by the electric field from surrounding atoms, ions, or molecules, affecting the spectral emissions of the species under study. In other words. the external electric field comes from other atoms and molecules. The other atoms and molecules are in constant motion, and so their electric fields are inhomogeneous in space and time. Instead of a frequency being split into several easily seen frequencies, the original frequency simply becomes much wider, encompassing all of what would have been the split frequencies. Remember our discussion on the effects of solvents and support materials? Yiany of those effects are the result of the intermolecular Stark effect.
The abo\·e examples demonstrated nicely how the Stark effect splits. shifts. and broadens spectral frequencies for atoms and molecules. The
intensities of the lines can also be affected. Some of these variations in intensity are shown in Figure 599• The intensity variations· depend on
rotational transitions, molecular structure, and the electric field strength.
o, (a) 2 3 4
u-
(b)
4
3
2
01
u-
Figure 59-i_ - Patterns of Stark components for transitions in the rotation of an asymmetric top
molecule. a) J = 4➔ 5 transition: b) J =-4➔4 transitions. The electric field is large enough for
complete spectral resolution.
An interesting Stark effect is seen in a structure such as a molecule, which has hyperfine frequencies. Remember our rule of thumb - the hyperfine frequencies result from an interaction between the electron and the nucleus. This interaction can be affected by an external electric field. If the external electric field is weak, then the Stark energy is much less than the energy of the interaction between electron and nucleus, ie. the hyperfine energy.9 The hyperfine lines are split into various new lines, and the separation between the lines is very small (low in frequency) compared to the original hyperfine splitting. This means that at low field strengths, the Stark effect produces Stark splitting at very low frequencies (radio and extra low frequencies).
If the external electric field is very strong, then the Stark energy is much larger than the hyperfine energy, and the molecule is tossed violently back and forth by the electric field. In this case the hyperfine structure is radically changed.9 It is almost as though there is no hyperfine structure. The Stark splitting is identical to that which would have been observed if there were no hyperfine frequencies, and the hyperfine frequencies simply act as a small
perturbation to the Stark splitting frequencies.
If the external electric field is intermediate. then the Stark and hyperfine
energies are equivalent. In this case, the calculations become very complex.
Generally, the Stark splitting is around the same frequencies as the hyperfine
splitting. but the relative intensities of the various components can vary
rapidly with slight changes in the strength of the external electric field. Thus.
at one electric field strength, a Stark frequency ·•A'" could predominate in
intensity, while at an electric field strength just l 0/o higher, a totally different
Stark frequency ..8 .. could predominate in intensity.
All of the preceding discussion on the Stark effect has concentrated on
the effects due to a static electric field, such as one would find with a direct
current. The Stark effects from a dynamic, or time-varying electric field
produced by an alternating current are quite interesting and can be quite
different. Just which of those affects appear. depends on the frequency of the
electric field (alternating current) compared to the frequency of the atom or
molecule in question. If the electric field is varying very slowly, such as with
60 Hz wall outlet electricity, then the normal or static type Stark effect occurs.
As the electrical frequency increases, the first frequency measurement
it will begin to overtake is the line width (see Figure 16 for a diagram of line
width). The line width of a curve is its' distance across, and the measurement
is actually a very tiny heterodyned frequency measurement of one side of the
curve minus the other side. Line width frequencies are around 100 KHz. In
practical terms, line width represents a relaxation time for molecules, where
the relaxation time is the time required for any transient phenomena to
disappear. So if the electrical frequency is a lot less than the line width
frequency, the molecule has plenty of time to adjust to the slowly changing
electric field, and the normal or static type Stark effects occur.
If the electrical frequency is just a little less than the line width
frequency the molecule changes its' frequencies, in rhythm with the frequency of the electric field. This is shown below in Figure 609 . As the electric field
frequency starts to get into the KHz line width range, the Stark curves vary
their frequencies with the electric field frequency and become broadened and
blurred.. When the electric frequency moves up and beyond the line width
range to 1200 KHz. the normal Stark type curves again become crisp and
distinguishable. In many respects. the molecule cannot keep up with the rapid
electrical field variation and simply averages the Stark effect. In all three
cases, the separation of the Stark frequencies is modulated with the electrical
fidd frequency. or its· first harmonic (2 X the electrical field frequency).
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0
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Fie1d $f1'1!11qtll (peak 'IOlt1/cn1 l
640 {q)
660 (bl
1200
9IO td
Figure 60¥. • Stark effect for OCS on the J = l ➔ 2 transition with applied electric fields at various
frequencies. a) The Stark effect with a static DC electric field: bl Broadening and blurring of the
Stark frequencies with a I KHz electric field: c) Normal Stark type effect\\ ith electric field of 1200 KHz.
The next frequency measurement that an ever increasing electrical
frequency will overtake is the transitional frequency betv.,een two rotational
levels. As the electric field frequency approaches a transitional frequency
between two levels, the radiation of the transitional frequency in the molecule
will induce transitions back and forth between the levels. The molecule
oscillates back and forth between both levels, at the freque.ncy of the electric
field. When the electric field and transition level frequencies are exactly
equal (in resonance), the molecule will be oscillating back and forth in both
levels, and the spectral lines for both levels will appear simultaneously and at
the same intensity. Normally, we would see only one level's frequency at a
time, but a resonant electric field causes the molecule to be at both levels at
essentially the same time, and so both transitional frequencies appear in its'
spectrum.
As if this weren't incredible enough, for sufficiently large resonant
electric fields, additional transition level frequencies can occur at regular
spacings equal to the electric field frequency. 9 Also, splitting of the transition
level frequencies can occur, at frequencies of the electric field frequency
diYided by odd numbers ( electric field frequency - fE - divided by 3, or 5, or
7. ie. t~ /3 or fE /5.)
Next we get to the fun part. which is explaining what all this has to do
with spectral catalysts. Electric fields cause the Stark effect. which is the
- - - - - 1/-9/ splittirur. shifting. broadening. or charn;rirnz '3"ntensitYf spectral frequencies
Page -99-
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for atoms and molecules. As with many of the other mechanisms we have
already discussed, changes in the spectral frequencies of reaction systems can
affect the reaction rate and reaction path. Let's say we have a reaction system
that looks like this:
C
C
where A & B are reactants. C is a physical catalyst. I stands for the interme-
diates. and D & F are the products.
Now suppose that the reaction nonnally progresses at only a moderate
rate, by virtue of the fact that the physical catalyst produces several frequen-
cies that are merely close to harmonics of the intermediates. Suppose that
when we add an electric field the catalyst frequencies are shifted so that now
several of the catalyst frequencies are exact harmonics of the intennediates.
This will catalyze the reaction at a faster rate. If we did not know about
spectral catalysts and the Stark effect we would probably come up with all
kinds of theories about the electric field promoting the catalyst and such, but
what it all boils down to is the simple idea of more efficient energy transfer
through matching resonant frequencies.
Now suppose that industrially it is known that the reaction nonnally
progresses at only a moderate rate, and so the industrial solution has been to
subject the reaction system to extremely high pressures. The high pressures
cause broadening of the spectral patterns, which improves the transfer of
energy through matching resonant frequencies. By understanding the
underlying catalyst mechanisms of the reaction, we could do away with the
high pressure system, and replace it with a simple electric field. Not only
would this be less costly to the industrial producer, it would be much safer for
the personnel to get rid of the high pressure equipment.
Some reactants when mixed together do not react very quickly at all, but
when an electric field is added they react rather rapidly. Traditionally, we
would say that the reaction is catalyzed by an electric field and the equations
would look like this:
E
A+BiD+F
And A+B ➔ D+F
where £ is the electric field. In this case. the physical catalyst "C'~ would
ha\·e been replaced by the electric field··£... We might be tempted to say that
instead of a spectral catalyst. we have an electrical catalyst. That would be a
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