DEPOLARIZED RAYLEIGH WING FROM RAMAN-SPECTRA AND LOCAL ORDER IN PURE C6H6 AND C6F6 LIQUIDS AND IN THEIR BINARY-MIXTURES

From Raman spectra, the low-wavenumber range profile (10-200 cm(-1)) of planar molecules C6H6, C6F6 and of their binary mixtures in the liquid state was recorded at intervals of 1 degrees C from 10 to 65 degrees 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 foe pure liquids. This effect is related to a change in tbe 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.