PRESSURE AND TEMPERATURE DEPENDENCES OF ABSORPTION IN THE NU(5) (R)Q(O) BRANCH OF CH3CL IN N-2 - MEASUREMENTS AND MODELING

The semiempirical approach developed in a previous paper is applied to the nu(5) (R)Q(0) branch of CH3CI perturbed by N-2. New experiments h ave been performed using a Fourier transform spectrometer with a resol ution of 0.016 cm(-1). Absorption has been measured for total pressure s and temperatures in the ranges 0.3-1.1 atm and 197-298 K, respective ly. It is shown that our model enables satisfactory prediction of pres sure and temperature, as well as wavenumber dependences of absorption, with 11 effective parameters which have been deduced from measured sp ectra. Analysis shows that the influence of line mixing on the absorpt ion shape is important down to total pressures of about 30 mbar and sh ould thus be accounted for in the treatment of atmospheric spectra. (C ) 1996 Academic Press, Inc.