Collisional-broadening coefficients in the ν₆ band of ¹²CH₃F perturbed by Ar

Ar-broadening coefficients are measured for 29 lines of CHF in the Q and Q branches of the ν band, using a tunable diode-laser spectrometer. The collisional widths obtained by fitting Rautian profiles to the measured shapes of the lines are significantly larger, especially for the overlapping lines at low-J values, than those obtained from Voigt profiles. The broadening coefficients for the lines belonging to the same low-J transitions (J = 7-10) appear to be greater in the Q branch than in the RQ branch. Comparisons have been made with calculated results based on a semiclassical model including adjustable potential parameters,