Theory of the low-temperature Seebeck coefficient in dilute alloys. II. The empty-core pseudopotential calculation

The Seebeck coefficient $S$ in dilute alloys at low temperatures is calculated for an impurity scattering potential derived from the empty-core pseudopotential. In the model considered here, free electrons are scattered by a random array of fixed impurities and interact with longitudinal phonons. The electron-phonon correction to $S$ in alkali-alkali alloys is found to be positive if an impurity is heavier than a solvent and negative otherwise. In most other alloys where the valence of the impurity and the solvent is different, the net electron-phonon enhancement of $S$ is found to be numerically close to the usual mass-enhancement ratio, in accord with the results in the case of the screened Coulomb potential.