Electronic Specific Heat in Dilute Alloys

Abstract

The change in the specific heat of a simple metal due to the introduction of a small number of impurity atoms with an excess valence Z over the host metal ion is calculated on the basis of the many-body perturbation theory. The fact that the impurity potential depends on temperature is found not to contribute to the specific heat. The result of numerical calculations shows that the magnitude of O(Z) is comparable with that of O(Z²). Next, the phase-shift method is considered. In order to investigate the oscillation term in the density of states, the screened charge in the large sphere containing a finite number of impurity atoms is directly calculated. It is found that the oscillation term is of the order of the reciprocal of the radius of the sphere.