Capillary waves and the inherent density profile for the liquid–vapor interface

The statistical mechanical theory of the density distribution through the liquid–vapor interface has been re-examined for single-component monatomic substances. Particles are covered by spheres with radii such that uncovered volume is globally connected throughout the vapor but disconnected throughout the liquid. This approach in turn allows: (1) identification of an ’’outermost layer’’ of particles on the liquid, (2) definition of capillary wave collective coordinates for the surface, and (3) recognition of an ’’inherent density profile’’ for the interface that for T