DIODE-LASER MEASUREMENTS OF ON-BROADENING COEFFICIENTS IN THE V(3) BAND OF CH3D

O-2-broadening coefficients have been measured for 29 lines of (CH3D)- C-12 in the P-Q and (Q)R branches of the v(3) band, using a tunable di ode-laser spectrometer. The collisional widths obtained by fitting Rau tian profiles to the measured shapes of the Lines are significantly la rger than those derived from Voigt profiles. A comparison is made with results calculated from a semiclassical impact theory of collisional broadening. In addition to the weak electrostatic contributions of the intermolecular potential, we have considered a simple formalism for t he other anisotropic interactions. (C) 1996 Academic Press, Inc.