Publications Details
Capillary waves at liquid-vapor interfaces: A molecular dynamics simulation
Evidence for capillary waves at a liquid-vapor interface are presented from extensive molecular dynamics simulations of a system containing up to 1.24 million Lennard-Jones particles. Careful measurements show that the total interfacial width depends logarithmically on L∥, the length of the simulation cell parallel to the interface, as predicted theoretically. The strength of the divergence of the interfacial width on L∥ depends inversely on the surface tension γ. This allows us to measure γ two ways since γ can also be obtained from the difference in the pressure parallel and perpendicular to the interface. These two independent measures of γ agree provided that the interfacial order parameter profile is fit to an error function and not a hyperbolic tangent, as often assumed. We explore why these two common fitting functions give different results for γ.