SPECTRUM OF DEPOLARIZED LIGHT SCATTERED BY LIQUID BENZENE DERIVATIVES

The spectrum of the depolarized scattered light from liquid nitrobenzene, aniline, benzonitrile, benzoyl chloride, bromobenzene and chlorobenzene at 23±2°C as measured by the pressure scanned Fabry-Pérot method is reported. It is shown that the proper analysis of the overlap effect in the Fabry-Pérot method and the use of a series of suitable spacers is helpful in the deduction of the true scattering spectrum especially for the wings. The spectra are found not to be Lorentzian in any of the liquids, nor are they Lorentzians corrected by an inertial effect but they can be represented reasonably well by the sum of two Lorentzians. If the spectrum is resolved into two Lorentzians the correlation time for the broad component is about ten times shorter than for the narrow component. The spectra differ significantly for the different liquids. The principle relaxation times for the fluctuations in the anisotropic refractive index, where the comparison is possible, are fortuitously comparable with those reported previously ([1, 2]) which did not properly allow for the overlap. These times are also longer than those deduced for molecular re-orientational motion from nuclear resonance and dielectric absorption but may be more comparable with those obtained from sound absorption. This appears to indicate that the depolarized light scattered by these liquids is controlled by the correlation function for the re-orientational motion of more than one molecule. © 1968 Taylor and Francis Group, LLC.