MANY-BODY ATOMISTIC MODEL POTENTIAL FOR INTERMETALLIC COMPOUNDS AND ALLOYS AND ITS APPLICATION TO NIAL

A technique for constructing many-body atomistic potentials based on a b initio data, designed for computer simulations of structural and the rmomechanical behavior of metallic systems is presented. This model po tential, which is based. on a simple mathematical transformation betwe en atomic volume and a local variable function, does not require any e xperimental input. All potential parameters have been determined by fi tting to energy surfaces (resulting from crystal structure expansion/c ontraction or deformation) calculated by ab initio total-energy calcul ations. As an illustrative example, we have successfully applied the s cheme to NiAl in the study of (100) surface relaxation and crystal pla sticity properties.