Self-broadening coefficients in the ν3 − ν1 band of CS 2

Abstract

The self-broadening coefficients of CS 2 at room temperature have been measured for 34 lines in the P- and R-branches of the ν 3 − ν 1 band, using a diode-laser spectrometer. These lines with J values ranging from 2 to 78 are located in the spectral range 857–888 cm −1. The collisional widths are obtained by fitting each recorded line with the Voigt profile as well as the Rautian profile accounting for the collisional Dicke narrowing effect. The latter model provides larger broadening coefficients than the Voigt model. These coefficients are also calculated from a semiclassical formalism involving for the intermolecular potential the quadrupole–quadrupole interaction in addition to a simple anisotropic dispersion contribution. The theoretical results are in reasonable agreement with the experimental data in view of the estimated uncertainties in these data.