Density dependence of interaction-induced scattering contributions to the depolarized Rayleigh band of ethane

Abstract

Depolarized Rayleigh and Raman ν₃(C—C stretch) spectra of ethane at 50 °C in the density range from 0.16ρ_c to 2.3ρ_c are reported (where ρ_c is the critical density). With the two pieces of information an attempt is made to separate orientational from non-orientational interaction-induced scattering contributions experimentally. The non-orientation spectra resemble in several respects the spectra obtained from atomic fluids such as argon. In particular, the low-frequency induced spectral intensity shows typical two-body–three-body cancellation effects with increasing density.