Influence of Electron Interactions on Metallic Properties. I. Specific Heat

Abstract

The specific heat of an intermediate density electron gas has been calculated by the use of a momentum-transfer interpolation procedure analogous to that used by Nozières and Pines in the calculation of the correlation energy. The explicit momentum transfer dependence of the derivative of the self-energy at the Fermi surface has been calculated in the long-wavelength limit by the use of the random-phase approximation, and in the short-wavelength limit by the use of second-order perturbation theory with the neglect of parallel-spin interactions. The contributions from the intermediate momentum-transfer interactions are determined by a smooth interpolation between the short- and long-range regions. The results obtained by this procedure are in excellent accord with the high-density results for $r_s\sim 1$, and in their application to the alkali metals predict the experimentally observed enhancement of the specific heat ratio.