“Leakage” effect as an exciting mechanism of high vibrational levels of polyatomic molecules by a strong quasi-resonant laser ir field

We present a very simple theoretical model aimed at the analysis of non-linear relaxation processes in molecular gases in the presence of partial molecular dissociation induced by vibrational–vibrational exchange between highly excited molecules. The model has a phenomenological character, since it analyzes the behavior of a system of anharmonic diatomic molecules, which is a very rough approximation of a polyatomic molecule such as SF6. Nonetheless, it provides an interesting key for the interpretation of a number of peculiar features characterizing our experimental observation, with which a comparison is made. In particular, the model takes realistic account of the influence of dissociation processes on the relaxation time.

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Diffuseness of the vibrational absorption spectra of polyatomic molecules due to sequence congestion of the vibrational levels

Journal of Applied Spectroscopy ◽

10.1007/bf00615669 ◽

1976 ◽

Vol 25 (6) ◽

pp. 1535-1541

Author(s):

S. O. Mirumyants ◽

Yu. S. Demchuk

Keyword(s):

Absorption Spectra ◽

Polyatomic Molecules ◽

Vibrational Absorption ◽

Vibrational Levels

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EXPERT SYSTEM FOR THRESHOLD SPECTRA ANALYSIS OF SO2 MOLECULES

International Journal of Modern Physics C ◽

10.1142/s0129183107011170 ◽

2007 ◽

Vol 18 (07) ◽

pp. 1133-1148 ◽

Cited By ~ 2

Author(s):

VIOLETA PETROVIĆ ◽

V. BOČVARSKI ◽

I. PETROVIĆ

Keyword(s):

Expert System ◽

Excited States ◽

Polyatomic Molecules ◽

Spectra Analysis ◽

Triatomic Molecules ◽

Low Intensity ◽

Electron Spectra ◽

Vibrational Levels ◽

Threshold Energies

In this paper an expert system is presented that was developed with the aim to analyze electron spectra on the threshold energies in collision with triatomic and polyatomic molecules. This expert system was made by updating the expert system for the analysis of the threshold spectra of two-atomic molecules. In contrast to the threshold spectra of two-atomic molecules, where were exist more or less defined structures of excited states, as well as vibrational levels, in the threshold spectra of triatomic molecules clearly defined structures almost do not exist. The application of the expert system in the process of triatomic and polyatomic molecules spectra analysis has an important role because it enables analysis of larger number of excited states, vibrational levels, and resonances, which can be missed in the analysis by classical methods, either because of low intensity or because of insufficiently defined separation of peaks in spectrum, which arise from the overlapping of a large number of peaks.

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Analytical Evaluation for Calculation of Two-Center Franck–Condon Factor and Matrix Elements

Journal of Chemistry ◽

10.1155/2018/3147981 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Hüseyin Koç

Keyword(s):

Transition Probabilities ◽

Polyatomic Molecules ◽

Harmonic Oscillators ◽

Binomial Coefficients ◽

Matrix Elements ◽

Molecular Physics ◽

Line Intensities ◽

Vibrational Levels ◽

Analytical Formulas ◽

Franck Condon

The Franck–Condon (FC) factor is defined as squares of the Franck–Condon (FC) overlap integral and represents one of the principle fundamental factors of molecular physics. The FC factor is used to determine the transition probabilities in different vibrational levels of the two electronic states and the spectral line intensities of diatomic and polyatomic molecules. In this study, new analytical formulas were derived to calculate Franck–Condon integral (FCI) of harmonic oscillators and matrix elements (xη, e−2cx, and e−cx2) including simple finite summations of binomial coefficients. These formulas are valid for arbitrary values. The results of formulas are in agreement with the results in the literature.

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