Depolarized rayleigh wing from Raman spectra and local order in pure C 6 H 6 and C 6 F 6 liquids and in their binary mixtures

From Raman spectra, the low‐wavenumber range profile (10‐200 cm −1 ) of planar molecules C 6 H 6 , C 6 F 6 and of their binary mixtures in the liquid state was recorded at intervals of 1°C from 10 to 65°C. The analysis was made using a reduced intensity ratio R involving the integrated intensity of a constructed I(v)v 2 spectrum and the recorded I(v) spectrum. The study of R against a slow and gradual variation of temperature emphasized a break in the gradient for pure liquids. This effect is related to a change in the local environment of the molecules. This break did not appear in the study of a 1:1 mixture owing to its strong stability due to a face‐to‐face configuration.