|MadSci Network: Physics|
1. NASA's Electromagnetic Spectrum web site:
2. Richard P. Feynman, Six Easy Pieces, Addison-Wesley, NY, 1995.
3. Mad Science Archives Question: Can a lens focus light to the temperature of the sun?
4. MadSci Archives Question: About fusion?
The simple answer to your question is yes, we can disintegrate molecules by exciting
them at their resonating frequencies, provided that you can couple enough power into
them to generate a very high temperature plasma of ionized atoms, electrons and
molecular parts. However, it is not necessary and not practical to use a resonant
frequency to produce a plasma. A plasma is a 4th state of matter at temperatures
greater than those of solids, liquids or gasses. In a gaseous plasma the atoms are
partially or wholly ionized (stripped of electrons). It is estimated that more than
99% of the matter in the universe is in the plasma state particularly in our sun, the
stars and nebulae. Because of the large number of resonance frequencies that molecules
and their atoms have we can use very high powered heating sources such as focused
sunlight at a French solar furnace (see Reference 3) or lasers at the Lawrence
Livermore National Laboratory's giant NOVA laser fusion facility that are used to heat
hydrogen to the temperature of the suns core(see Reference 4.).
Your question is related to a number of factors concerning how atoms and molecules
interact , including temperature, pressure and the structure of the atoms and the
molecule. In the first chapter of Reference 2., which is available in paper back in many
book stores, the late Nobel Laureate Professor Feynman, writes:
"If, in some cataclysm, all of scientific knowledge were to be destroyed and only one
sentence passed on to the next generation of creatures, what statement would contain
the most information in the fewest words? I believe it is the atomic hypothesis (or
the atomic fact, or what ever you wish to call it) that all things are made of
atoms-little particles that move around in perpetual motion, attracting each other
when they are a little distance apart, but repelling upon being squeezed into one
another. In that one sentence, you will see that there is an enormous amount of
information about the world, if just a little imagination and thinking are applied."
Professor Feynman also goes on to say that atoms are very, very small. If we could
magnify an apple up to the size of the earth the atoms would be about the size of an
Professor Feynman starts his discussion atoms and molecules using the melting and
boiling of water molecules which are composed of two small hydrogen atoms and one
large oxygen atom. At very low temperatures water is a solid (ice). The hydrogen
atoms of the water molecules are all stuck (bonded) to each other by attraction and
although the atoms are all vibrating as if they are attached by springs, they are
all trapped in a fixed location in the solid ice crystal. As the temperature is
increased the vibrations become more violent until near zero degrees Celsius (32 F)
the molecules break loose from each other (melt) and liquid forms. The hydrogen's
still attract each other but the molecules are free to move about sharing hydrogen
bonds with each other as they move (flow). If we raise the temperature to 100 degrees
Celsius (212 F) the liquid begins to boil and the molecules are vibrating so violently
that they break loose from each other and expand in rapid motion and form a gas (steam).
If you measure the melting points and boiling points of the 100 plus elements you will
find a huge range of temperatures. For example helium (He) boils at 0.9 degrees above
absolute zero (-273.15 C) and tungsten (Wf) melts at 3422 C and boils at 5555 C (10031F)!
Mercury (Hg) and gallium (Ga) can exist at one atmosphere pressure in three different
states; sold, liquid and gas (some scientists would add a fourth state, the highly
excited plasma state). The state in which a group of atoms exists is dependent on a
number of factors including the temperature and the pressure. Solids are further
complicated because they form in seven different crystal systems. These crystal
structures define the optical, electrical, thermal, magnetic and elastic properties
of the atoms in the crystal. Many molecules can exist in several crystalline states
called phases, each with different physical properties. Another interesting fact is
that Hg melts at -38.84 C and boils at 356.73 C while Ga also melts near room
temperature at 30 C but boils at 2205 C, a temperature eight times higher than Hg.
Thus while the two metals have solid state bonds that break near room temperature,
Ga has much stronger bonds in the liquid state.
The ionization potential of an atom or ion is the amount of energy required to remove
one electron from one atom when it is in its normal state, leaving the next higher
ion in its normal state. The element with the lowest ionization potential is cesium (Cs)
with a value of 3.89 electron volts (ev) and 25.1 ev to ionize the second electron.
Helium has the highest ionization potential at 24.58 ev for the first electron and
54.4 ev for the second electron. These high values are one of the reasons why
thermonuclear fusion as discussed in Reference 4 is so difficult to obtain using lasers
in a closed container and not with a hydrogen bomb. The water vapor molecule has an
ionization potential of 13.2 ev.
Resonant Atomic and Molecular Frequencies:
All molecules, depending on the number of protons in the nucleus and the number of
atoms in the molecule, and the temperature and pressure, have hundreds to thousands
of resonant frequencies many of which can over lap. These resonance frequencies occur
between the protons and electrons within an atom and between the atoms within the
molecule. Thus if the atoms have a large number of protons and electrons there can
be very many resonant interactions. These resonances occur at frequencies through out
the electromagnetic spectrum from radio frequencies to microwaves to infrared waves,
to visible light to ultraviolet waves etc. (see Reference 1).
Let us continue to use the relatively small water molecule (H2O) as an example. In
the solid and liquid state it is difficult to detect these molecular resonances
because they are highly damped by the closeness of the molecules and the low
temperatures involved; although, medical magnetic resonance imaging (MRI) does use a
spin resonance in the water molecule using high magnetic fields. If the water is in
the form of a gas (steam or water vapor) we can detect molecular resonant absorption
frequencies around 24 GHz, 180 GHz and 320 GHz (Note: 1 Gigahertz (GHz) = one billion
cycles per second) in the microwave frequency region of the spectrum. At normal
atmospheric pressure these resonances are pressure broadened to be several GHz wide which
is not very sharp. At lower pressures more sharp resonances can be detected.
The U.S. time and frequency standard consists of a group of about 20 atomic clocks that
use a resonance near 10 GHz in the cesium (Cs) atom by probing Cs beams in a vacuum.
These resonances are detected at microwatt levels and they are now being flown on board
each Global Positioning System (GPS) navigation satellites. These spceborne atomic
clocks are synchronized by even more accurate hydrogen maser atomic clocks on earth that
measure a nanowatt nuclear resonance at 1.420 GHz in a beam of hydrogen atoms at very
There are an increasing number of molecular resonances through out the infrared
region of the spectrum. However, at visible frequencies, ultraviolet frequencies and
above the resonances are between electron orbits within each atom. Lasers use these
phenomenon to generate electromagnetic energy at very specific specific frequencies.
To generate a plasma of water vapor we must heat the gas to very high temperatures.
We can use microwave heating techniques, giant mirrors to focus sunlight on the vapor
or very high powered lasers to reach plasma temperatures required to ionize and
break up the water molecules into ionized hydrogen and oxygen atoms. The only practical
use that I am aware of for generating a water vapor plasmas is to remove films of
degrading substances off of mirrors an thermal radiators without scratching them.
Best wishes for the New Year, Your Mad Scientist
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