Force constants for substitutional alloys

Recently, the importance of the vibrational aspects of alloy phase stability has attracted much interest. There is much controversy over the extent to which the vibrational free energy affects order-disorder temperatures and other phase equilibria. Here, we examine the feasibility of defining transferable force constants for an alloy in much the same spirit as tight-binding Slater-Koster parameters can be defined for substitutional alloys. In particular, the predictive ability of such alloy specific, but configuration independent, force constants for the elastic, relaxation, and vibrational properties is examined.