SUSCEPTIBILITIES OF LIQUID-VAPOR INTERFACE OF SIMPLE LIQUIDS

Quantities related to two-point correlation function in the inhomogene ous interfacial zone of a planar liquid-vapor interface are determined from molecular dynamics simulations for a Lennard-Jones liquid at equ ilibrium with its vapor at the reduced temperature kT/epsilon=1.0. Sus ceptibilities and density fluctuations in planes parallel to the inter face are reported. Stabilization of the liquid slab surrounded by vapo r, by an external potential, is also discussed. Qualitative agreement was found for the contribution predicted from capillary-wave theory-in contrast to the case of liquid-liquid interface(8) at low temperature , where fully quantitative agreement was obtained. (C) 1996 American I nstitute of Physics.