Curvature Jump at the Facet Edge of a Crystal for Arbitrary Surface Orientation

Abstract

The equilibrium crystal shape (ECS) for the body-centered solid-on-solid (BCSOS) model in the low-temperature phase is studied. Based on the equivalence between the BCSOS model and the asymmetric six-vertex model, the surface free energy f(ρ) (ρ: step density) is calculated for general mean surface tilt angle. In the expansion, f(ρ )=f(0)+α ρ+βρ³+O(ρ⁴), the universal relation between a and b is verified. Accordingly, the Gaussian curvature of the ECS is shown to assume a universal finite jump at any position of the facet edge of the crystal.