Molecular dynamics simulation of a small drop of liquid argon

Abstract

Results for molecular dynamics simulation method of small liquid drops of argon (N = 1200-14400 molecules) at 94.4 K through a Lennard-Jones intermolecular potential are presented in this paper as a preliminary study of drop systems. We have calculated the density profiles ρ(r), and from which the liquid and gas densities ρg, the position of the Gibbs' dividing surface Ro, the thickness of the interface d, and the radius of equimolar surface Re can be obtained. Next we have calculated the normal and transverse pressure tensor pN(r) and pT(r) using Irving-Kirkwood method, and from which the liquid and gas pressures pl and pg, the surface tension γs, the surface of tension Rs, and Tolman's length d can be obtained. The variation of these properties with N is applied for the validity of Laplace's equation for the pressure change and Tolman's equation for the effect of curvature on surface tension through two routes, thermodynamic and mechanical.