ROUGHNESS INFLUENCE ON SURFACE MELTING

Abstract

The influence of surface roughness on surface melting phase transition is discussed within the molecular field theory. The roughness is characterized by the surface order parameter averaged over all the density fluctuations whose description corresponds to the discrete Gaussian solid-on-solid model. The potential governing the transition between the rough surface and the surface melting is considered in terms of the modified van der Waals equation of state. Its effective shape represents two intersecting parabolas with nonequal curvatures for the solid and liquid phases. The phase diagram shows the coexistence of two phases with rough and wet surfaces.