bcc Symmetry in the Crystal-Melt Interface of Lennard-Jones Fluids Examined through Density Functional Theory

Abstract

Using a density functional theory for Lennard-Jones fluids, we find significant bcc (body-centered-cubic) character in both the planar interface between the stable fcc (face-centered-cubic) crystal and the stable liquid and at the interface of the critical fcc nucleus in a metastable liquid. We introduce an order parameter that continuously distorts a crystal with fcc symmetry to one with bcc symmetry. Our results suggest that metastable phases may have large effects on equilibrium interfaces and on rates of first-order phase transitions.