Reconstructions and Morphological Instabilities of FCC (110)Surfaces

We compare the ground state energy of the following structures of fcc (110) surfaces: the (1×1) flat surface, the (n×1) reconstruction (2 ≤ n < ∞), and the (∞ × 1) structure where the surface is faceted into macroscopic (111) surfaces. We map out the phase diagram using a lattice model with pair and triplet interactions. We argue that it is unlikely that any realist pair potential will give a reconstructed ground state. We also doubt that including, in addition, three body interactions will stabilize the reconstructed structure for interatomic interactions derived from the embedded atom method.

THREE-SPIN CORRELATION OF THE ISING MODEL ON A KAGOMÉ LATTICE

Several local three-spin correlations are derived for the Ising model on a Kagomé lattice with anisotropic pair interactions. Three-spin correlation for three spins surrounding a triangle is derived for the Kagomé lattice Ising model with isotropic pair and triplet interactions at a particular temperature determined by pair interaction only.