TEMPERATURE DEPENDENCE OF $N_{2}$-BROADENING COEFFICIENTS IN THE $v_{3}$ BAND OF OZONE
Loading...
Date
1991
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
We report the first measurements of the temperature dependence of the nitrogen broadening coefficients of selected ozone rovibrational transitions. We recorded spectra of the $v_{3}$ band at approximately 1000 $cm^{-1}$ with a Bomem Fourier transform spectrometer at a resolution of $0.004 cm^{-1}$ and broadened by nitrogen at pressures ranging from 0 to 80 torr. The temperature was varied over the range of 180 K to 296 K in 20 K increments from one set of broadend spectra to the next. The pressure broadening coefficient, $\gamma$(T), for a particular transition at a temperature, T, was obtained as the slope of a straight line plot of the collision broadened half-width vs. added nitrogen pressure. The dependence of the pressure broadening coefficient was assumed to be given by the power law, $\gamma(T)/\gamma(T_{0}) = (T/T_{0})^{-n},$ where $T_{0}$ is a reference temperature (296 K) and n is the temperature exponent. A plot of In $(\gamma (T))$ vs. In(296 K/T) therefore yields n. Values of n have been obtained for approximately 30 transitions in the $v_{3}$ band and are close to the theoretically predicted average value of 0.76. We compare our experimentally determined temperature coefficients to those predicted by Quantum Fourier Transform $theory^{1}$.
Description
$^{1}$R. Gamache, J. Mol. Spectrose. 114, 31 (1985).""
Author Institution: NASA AMES Research Center; NASA AMES Research Center
Author Institution: NASA AMES Research Center; NASA AMES Research Center