Determination of structural alloy equilibrium properties from quantum approximate methods

Abstract

In this paper we address basic issues, not investigated previously, concerning the relationship between ab initio methods and the Bozzolo-Ferrante-Smith (BFS) method for alloys, and its ability to model the process of alloy formation and reproduce structural alloy properties near and at equilibrium. Based on perturbation theory, the method requires single element parameters and their binary combinations, even for multicomponent systems. A direct comparison of BFS predictions of equilibrium alloy properties against ab initio results, and the handling and influence of the parameterization on the accuracy with which the method reproduces the process of alloy formation are presented. Besides establishing a range of validity for the method in reference to first-principles results, a simple algorithm for the determination of equilibrium properties of ordered alloy systems is introduced and illustrated with applications to binary and higher order systems, maximizing the flow of information carried in the first-principles-based parameters.