Static conductivity of a binary alloy in the traveling-cluster approximation

A study is made of the problem of finding the static electrical conductivity of a binary alloy in the tight-binding model with offdiagonal disorder in the presence of short-range order in the system. A general scheme is proposed for constructing selfconsistent approximations for averaged products of two Green's functions in order to determine the kinetic properties of disordered alloys. The approach corresponds to the traveling-cluster approximation used to find the electron spectra of binary alloys. The augmented-space formalism provides the framework for the treatment.