Item – Theses Canada

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OCLC number
46503540
Author
Zhu, Chenxi,1969-
Title
Internal rotation in the overtone spectra of fluorotoluenes.
Degree
M. Sc. -- University of Guelph, 1996
Publisher
Ottawa : National Library of Canada = Bibliothèque nationale du Canada, 1996.
Description
2 microfiches.
Notes
Includes bibliographical references.
Abstract
The vapour phase overtone spectra of several fluorotoluene molecules (2,6-difluorotoluene, 3,5-difluorotoluene, 2,3,5,6-tetrafluorotoluene, 2,3,4,5,6-pentafluorotoluene) have been recorded with conventional absorption spectroscopy in the $\rm{\Delta V}\sb{CH}=2$ and 3 regions and with intracavity laser photoacoustic spectroscopy in the $\rm{\Delta V}\sb{CH}=4$ to 6 regions. These spectra are analyzed with the help of ab initio calculations. It is concluded that methyl near free rotation, especially the coupling between the methyl rotation and CH stretching, is the cause of the complex structure observed in the methyl overtone region. A model has been developed to calculate these overtone spectra, which takes into account in the adiabatic approximation the coupling between CH stretching (described by the harmonically coupled anharmonic oscillator model) and methyl rotation (described by the free rotor model). This model provides a theoretical framework for the analysis of overtone spectra of molecules with internal rotation. Intramolecular vibrational relaxation of the methyl group has also been discussed.
ISBN
0612097625
9780612097629