A structural model for the solid-liquid interface in monatomic systems

Abstract

A structural model for the solid-liquid interface has been developed by applying the construction rules for the liquid to the boundary condition of a crystal plane. In particular, an interface has been created between a dense random packing of hard spheres and a close packed crystal plane by preferentially forming tetrahedral holes (typical for the liquid) and disallowing octahedral holes (necessary for the crystal). The resulting interface has zero density deficit in agreement with conclusions from positron lifetime studies. The surface tension, of entropic origin, is of the same magnitude as the experimental values. The model can account qualitatively for the ease of step nucleation during crystal growth.