Measurement and computations for temperature dependences of self-broadened carbon dioxide transitions in the 300124 <- 00001 and 30013 <- 00001 bands

A. Predoi-Cross
W. Liu
R. Murphy
V. Malathy Devi, William & Mary

Abstract

Using a Fourier transform spectrometer setup we have measured the self-broadened half width, pressure shift, and line asymmetry coefficients for transitions in the 30012 <- 00001 and 30013 <- 00001 vibrational bands of carbon dioxide for four different temperatures. A total of 46 pure CO2 spectra were recorded at 0.008 and 0.009 cm(-1) resolution and at pressures varying from a few Tort to nearly an atmosphere. The individual spectral line profiles have been fitted by a Voigt profile and a speed-dependent Voigt profile, to which we have added dispersion profiles to account for weak line mixing. A comparison of the sets of results obtained for each band showed no vibrational dependence of the broadening coefficients. The self-broadening and self-shift coefficients are compared to semiclassical calculations based on the Robert-Bonamy formalism and were found to be in good agreement. The line asymmetry results are compared to line mixing calculations based on the Energy Corrected Sudden (ECS) and Exponential Power Gap models. (C) 2010 Elsevier Ltd. All rights reserved.