Orientational correlation in molecular liquids estimated from experimental structure factors

Abstract

Orientational correlation and molecular center distribution are two fundamental quantities describing the structure of molecular liquids. The two quantities estimated directly from the experimental structure factors, S m( Q), of simple molecular liquids composed of dumbbell or tetrahedral molecules are summarized. In comparison with this, a more complicated molecular liquid, antimony trichloride (SbCl 3), has been examined, in which the molecular interaction seems to be very anisotropic compared with that for the simple molecular liquids. An analysis of both the neutron S M( Q), measured by pulsed neutron diffraction, and the X-ray S m( Q) reported in the literature has suggested that there are at least two different preferred orientations in liquid SbCl 3: nearly parallel and anti-parallel configurations of the pyramidal axes of the molecules. The molecular center distribution of liquid SbCl 3 seems to be much distorted from that of simple molecular liquids.