On the location of surface of tension in the planar interface between liquid and vapour

Abstract

The structure of the interface of an argon-like fluid in equilibrium with its own vapour at 110 K is studied using the Monte Carlo method. The two components P _N(z) and P _T(z) (normal and tangential) of the pressure tensor P(r) for the planar interface are determined in the simulation. The normal component is a constant along the direction perpendicular to the surface (the z-direction) and is equal to the hydrostatic pressure. The tangential component varies across the surface. The surface tension γ, and the surface of tension z _s are determined. The location of the surface of tension is compared with the location of the Gibbs equimolar dividing surface, and the results are used to determine the curvature dependence of the surface tension for spherical droplets. The results are compared with theory.