A methane molecule adsorbed on a graphite surface

Abstract

In this paper we present a molecular dynamics study of a methane molecule adsorbed on a graphite surface. The methane is modelled using five interaction sites and the surface is an infinite hexagonal array of carbon atoms. The potential parameters are fitted using static calculations to the rotational barrier heights and using molecular dynamics to the isoteric enthalpy at zero coverage. The effective pairwise potential predicts the height of the monolayer above the surface and the vibrational frequency against the surface. We have examined the translational and rotational behaviour of a single methane molecule across the surface.