Molecular dynamics calculations of the time dependence of simple anisotropic potentials in dense argon

Abstract

Molecular dynamics calculations on the time dependence of the anisotropic potential experienced by a probe molecule in argon, are presented. The calculations were performed for Ar densities of 100, 300, 500 and 784 amagat and T = 160 K. Collective motions clearly manifest themselves at higher densities, in particular in the power-spectrum of the part of the anisotropic potential that transforms as an irreducible tensor of rank 1. The relation between time-dependent local anisotropy and a number of experiments is discussed.