Statistical Mechanical Calculations of Molecular Pair Correlation Functions and Scattering Intensities

Abstract

AbstractFor the case of special molecular models representing the acetonitrile molecule the expansion coefficients of the molecular pair distribation function are calculated by use of perturbation theory. These results are used to get theoretical access to scattering intensities in the frame of several approximations. The first model describes the molecule by three hard spheres and uses a hard sphere liquid as a reference. In the second case the calculations are based on an anisotropic Lennard‐Jones potential by application of a model of overlapping ellipsoids and by use of a Lennard‐Jones liquid as a reference system. In the third model dipolar attractive forces are taken into account with an anisotropic hard‐sphere liquid as a reference. Finally all the calculations with different intermolecular potentials are compared with neutron scattering experiments.