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The Infrared spectra and quantum hypothesis

The Infrared spectra problem (and quantum hypothesis)

Background and actual explanation

The hydrogen and other gases spectrum, obtained as result of electric discharge in rarefied gases, were studied before the advance of quantum mechanic theory. Since the hydrogen atom has only one orbital electron surrounding a nucleus consisting of a single proton, it has a particularly simple spectrum.
The explanation of hydrogen spectra was considered one of earliest success of Quantum mechanics (QM).
It is not the case to enter into details of initial Bohr theory or in further advanced quantum theory related to this subject.
For the present discussion it is important to remind the existence of some experimentally observed series of spectrum lines in different region of electromagnetic spectrum, and the conviction that actual quantum mechanic is able to explain them in a consistent way.



Series Expression      





Near UV & Visible   











In all quantum theories, an infrared hydrogen line is produced as result of an electron quantum jump between two states corresponding to an excited and ground state. In more simpler and intuitive words, an IR photon as example, is produced as result of electron jump between two close orbits in case of Bohr theory (fig. 1), or in case of two close orbital energy in case of modern quantum theory.
Figura 1. Hydrogen atom excitation by an IR photon
An IR photon is not able (does not have enough energy) to produce ionization, or to move the entire atom of hydrogen. As is well known the proton is approx. 2K times heavier then electron so, from a common sense interpretation, even the photon will knock the nucleus, the movement of a hydrogen atom is insignifiant in actual quantum theory.
But it seems that for our theoreticians different chapters of the same quantum theory are in fact different theories.
If someone read the actual quantum mechanic interpretation of molecules IR spectrum remains astonished about the consequences of an IR photon acting on a bigger molecule.
Infrared, or IR, spectroscopy is one type of vibrational spectroscopy, where molecular vibrations are analyzed. To fully understand IR spectroscopy, you must first understand the principles of simple harmonic motion from classical mechanic.

A simple harmonic oscillator is formed by two spheres, or masses, connected with a spring. Once set into motion, the sphere will oscillate, or vibrate back and forth on the spring, at a certain frequency depending on the masses of the spheres and the stiffness of the spring. A sphere with a small mass is lighter and easier to move around than one with a large mass. Therefore, smaller masses oscillate at a higher frequency than larger masses. A very stiff spring, is hard to deform and quickly returns to it's original shape when the deforming force is removed. On the other hand, a weak spring is easily deformed and takes much longer to return to it's shape. Therefore, a stiffer spring will oscillate at a higher frequency than a weak one. A chemical bond between two atoms can be thought of as a simple harmonic oscillator. The bond is the spring, and the two atoms, or groups of atoms, connected by the bond are the masses. Every atom has a different mass, and single, double and triple all have different stiffnesses, and therefore each combination of atoms and bonds has its own characteristic harmonic frequency.
According to actual quantum hypothesis, there is a background oscillatory motion of all atoms in a molecule when this molecule is at a temperature greater then 0K. If a vibrating molecule is exposed to IR light, it will absorb those frequencies in the light which exactly match the frequencies of the different harmonic oscillators that make up that molecule. When this light is absorbed, the little oscillators in the molecule will continue to vibrate at the same frequency, but since they have absorbed the energy of the light, they will have larger amplitude of vibration. This means that the "springs" will stretch further than before the light was absorbed. The remaining light which was not absorbed by any of the oscillators in the molecule is transmitted through the sample.

As result of IR photon acting over a molecule the following motions for an atom or a group of atoms is possible:
• symmetrical stretching
• antisymmetrical stretching
• scissoring
• rocking

• wagging

• twisting

Why the actual explanation is absurd…..

It is necessary in a first step to evaluate the effects of quite equal infrared photon energy in the up presented cases.
In case of hydrogen atom the IR photon produces only a flip of electron from an orbit (or orbital) to another orbit (or orbital) as in fig. 1. The IR radiation is not strong enough to move the entire atom and in fact all quantum mechanics theories admit the immobility of nucleus during electron jump. If the IR photon hit directly the hydrogen nucleus, there is no enough energy to have a macroscopic effect.
But what’s happened in case of IR molecule spectra?
Quite the same IR energies produce an unimaginable result. An entire atom (electrons and nucleus), or an entire groups of atoms execute different kinds of movements from stretching to twisting.
It is possible to accept as real this atom or group of atoms change of position?
If we keep the proportion and translate the phenomena to the real world it is similar to saying that a fly knock a car and the car is forced to leave the road.
If a correlation between effects of IR and X-ray photons is made, other vexatious problems appear looking in the frame of quantum mechanics.
An X-ray photon is able to liberate electrons from a material. Why X-ray is not able to liberate an entire nucleus? Why a IR energy photon is able to move an atom but is not able to liberate an electron from a material?
If an IR photon is able to move an atom, it should be observed how an X-ray or gamma ray, with a greater energy, should expel an entire nucleus.
On the other hand, does anyone asks how is possible for an atom (with its layers of electrons)  jump ,,in a single step" from one position to another position? For a simple electron, when make a jump between two layers it can be admitted, according to quantum mechanic, the single step movement or cuanta of action. For an entire atom it is quite impossible to have a single step process. Up to date, there are no scientific texts which treat in detail this subject – quantum atomic jump – so the quantum theoreticians can use their imagination in order to fill this void.
In proposed theory as was already highlighted the quantum hypothesis is ruled out. In the same time there is a correlation between energy of incident photons and the observed effects and the spectra needs a new interpretation.