Depolarised light scattering from gases of anisotropic molecules at intermediate pressures

Abstract

Measurements are reported of the depolarisation ratios of argon, nitrogen, carbon dioxide and carbonyl sulphide over a range of gas pressures up to 100 bar. The density dependence of the depolarisation ratio is represented as a virial series and the second depolarisation virial coefficients for the gases have been calculated. It is found that the principal contribution to the depolarisation virial coefficients of carbon dioxide and carbonyl sulphide arises from density fluctuations, but the contribution from angular correlation and collision induced polarisability anisotropy may also be determined.