COLLISIONAL-BROADENING COEFFICIENTS IN THE NU(6) BAND OF (CH3F)-C-12 PERTURBED BY AR

Ar-broadening coefficients are measured for 29 lines of CH3F in the (R )Q(0) and (R)Q(6) branches of the upsilon(6) band, using a tunable dio de-laser spectrometer. The collisional widths obtained by fitting Raut ian profiles to the measured shapes of the lines are significantly lar ger, especially for the overlapping limes at low-J values, than those obtained from Voigt profiles. The broadening coefficients for the line s belonging to the same low-J transitions (J = 7-10) appear to be grea ter in the (R)Q(0) branch than in the (R)Q(6) branch. Comparisons have been made with calculated results based on a semiclassical model incl uding adjustable potential parameters. (C) 1998 Academic Press.