Energy dependence of the electron gas vertex function and its effect on transport properties

Abstract

The matrix element of the screened electron-ion interaction for the Fermi surface scattering is examined in terms of its rigorous form. Such a form includes the electron gas vertex function, which is energy dependent. The effect of this energy dependence on the thermoelectric power is estimated and shown to be very small. Thus the usual neglect of this intrinsic many-body energy dependence in the scattering functions is shown to be justified.