Molecular dynamics study of a dense fluid at a hard wall

Abstract

The structure and dynamics of a fluid in contact with a structureless “hard” wall have been determined for a state close to the freezing transition. The fluid particles interact via an inverse-twelfth-power pair potential, and the system has been studied using the molecular dynamics simulation method.

A pronounced layered structure formed parallel to the wall, but the pair distribution function (p.d.f.) within the layers may be well described, to a first approximation, by the bulk pair distribution function. The p.d.f. for the layer closest to the wall may be well described by the p.d.f. of the equivalent two-dimensional system. Although there was no evidence of heterogeneous nucleation, criteria are given which must be satisfied if heterogeneous nucleation and crystallisation are to be observed in a molecular dynamics simulation.