Theory of the conductivity of ordered alloys

A theory of the electrical conductivity of alloys going beyond the coherent potential approximation and taking into account statistical correlations in the scattering of the electrons by the atoms is developed. The two-particle Green's function for the electrons is calculated with allowance for scattering by pairs of atoms (the zeroth approximation corresponds to the coherent potential approximation), the correlations being described by means of the parameters of the short- and long-range order. It is shown that the change in the electron spectrum on ordering leads to a significant change of the alloy conductivity.