IR spectrum of highly vibrationally excited osmium tetraoxide in the region of strong nonlinear interaction of vibrational modes

Abstract The pure rotational spectra of molecules in 21 vibrationally excited states of the heterocyclic compound furazan (C2H2N2O) have been detected and studied by DRM microwave spectroscopy. Rotational parameters are reported for the 12 fundamental levels below 1500 cm-1 , and the contri-butions from 10 vibrational modes to the effective rotational constants and to the inertia defect of furazan are calculated.

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Picosecond Anti-Stokes Raman Excitation Profiles as a Method for Investigating Vibrationally Excited Transients

Laser Chemistry ◽

10.1155/1999/21312 ◽

1999 ◽

Vol 19 (1-4) ◽

pp. 335-341 ◽

Cited By ~ 1

Author(s):

Hiromi Okamoto ◽

Takakazu Nakabayashi ◽

Mitsuo Tasumi

Keyword(s):

Vibrational Energy ◽

Vibrational Modes ◽

Vibrational States ◽

Vibrationally Excited ◽

Quantum Numbers ◽

Trans Stilbene ◽

Raman Process ◽

Vibrationally Hot Molecules ◽

Raman Excitation Profiles ◽

Anti Stokes

A method for estimating vibrational quantum numbers of vibrationally excited transients in solution is proposed. In this method, we calculate anti-Stokes Raman excitation profiles (REPs) which are characteristic of the initial vibrational states involved in the Raman process, and compare them with observed anti-Stokes intensities. We have applied this method to vibrationally hot molecules of canthaxanthin in the So state and those of trans-stilbene in the S1 state. For canthaxanthin, it has been found that the vibrationally excited transients are for the most part on the ν=1 level of the C═C stretching mode, and that excess vibrational energy is statistically distributed among all intramolecular vibrational modes. As for S1 stilbene, vibrational transients are shown to be mostly on the ν=1 level for two vibrational modes examined, while the excess vibrational energy is probably localised on the olefinic C═C stretching mode.

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Etude à basse température dans l'infrarouge proche du dimère (NO)2

Canadian Journal of Physics ◽

10.1139/p84-048 ◽

1984 ◽

Vol 62 (4) ◽

pp. 322-329 ◽

Cited By ~ 36

Author(s):

V. Menoux ◽

R. Le Doucen ◽

C. Haeusler ◽

J. C. Deroche

Keyword(s):

Excited State ◽

Gas Phase ◽

Ground State ◽

Near Infrared ◽

Heat Of Formation ◽

Wave Number ◽

Vibrational Modes ◽

Vibrationally Excited ◽

Rotational Constants ◽

Absorption Intensity

The spectrum of the dimer (NO)2 in the gas phase has been studied in the near infrared at temperatures between 118 and 138 K. More specifically, the measure of absorption intensity of the ν4 and ν1 + ν4 bands has yielded the heat of formation of the dimer, −2.25 kcal/mol at 128 K, and revealed the influence of the low vibrational modes on this measure. The observation of the ν4 – ν6, difference band has yielded the wave number value of the ν6, fundamental band, forbidden in the infrared. The rotational constants of the vibrationally excited state were found to be larger than the ground state rotational constants, this result being very unusual.

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Evolution of the homogeneous IR spectrum of a highly vibrationally excited molecule as a result of a change in its vibrational energy

Applied Physics B Photophysics and Laser Chemistry ◽

10.1007/bf00697341 ◽

1988 ◽

Vol 47 (3) ◽

pp. 229-232 ◽

Cited By ~ 7

Author(s):

S. I. Ionov ◽

A. A. Stuchebryukhov ◽

V. N. Bagratashvili ◽

V. N. Lokhman ◽

G. N. Makarov ◽

...

Keyword(s):

Ir Spectrum ◽

Vibrational Energy ◽

Excited Molecule ◽

Vibrationally Excited

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The collisional deactivation of highly vibrationally excited pyrazine by a bath of carbon dioxide: Excitation of the infrared inactive (1000), (0200), and (0220) bath vibrational modes

The Journal of Chemical Physics ◽

10.1063/1.475666 ◽

1998 ◽

Vol 108 (7) ◽

pp. 2744-2755 ◽

Cited By ~ 29

Author(s):

Chris A. Michaels ◽

Amy S. Mullin ◽

Jeunghee Park ◽

James Z. Chou ◽

George W. Flynn

Keyword(s):

Carbon Dioxide ◽

Vibrational Modes ◽

Vibrationally Excited

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Observation of Intermode Coupling in the 3μm IR Multiple Photon Excitation of Propylene

Laser Chemistry ◽

10.1155/lc.1.177 ◽

1983 ◽

Vol 1 (5) ◽

pp. 177-183 ◽

Cited By ~ 2

Author(s):

R. L. Woodin ◽

C. F. Meyer

Keyword(s):

Energy Deposition ◽

Excited Molecule ◽

Vibrational Modes ◽

Vibrational States ◽

Vibrationally Excited ◽

Laser Chemistry ◽

Methyl Group ◽

Photon Excitation ◽

Deuterium Substitution

The mechanism of IR multiple photon excitation through the dense manifold of vibrational states, usually called the quasicontinuum, of a vibrationally excited molecule is one of the unresolved issues in the field of laser chemistry. The effects of deuterium substitution on propylene IR multiple photon excitation are used to identify the vibrational modes leading to efficient excitation. Optoacoustic energy deposition data show that for propylene, 3 μm multiple photon excitation occurs most efficiently at the methyl group, and furthermore that efficient methyl group excitation requires the CH group on the adjacent carbon. Thus 3 μm multiple photon excitation of propylene, while involving energy deposition directly into several spatially discrete intramolecular groups, is found to be enhanced by specific intramolecular couplings. Implications of this result for mechanisms of IR multiple photon excitation are discussed.

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