Second-Neighbor Interactions and the Critical Behavior of Binary Solid Solutions

Abstract

The Thiele semi-invariants γ1, γ2 and γ3 of a binary solid solution are calculated with the assumption that there are second-neighbor interactions as well as first-neighbor interactions. The results give a decrease of the critical temperature Tc at which the superlattice sets in, an increase of the local order σ at Tc, an increase of the discontinuity of the specific heat, thus in general agreement with the results obtained by applying Bethe's method to the same problem.