Electronic thermal resistivity of potassium and lithium

Abstract

Calculations of the electronic thermal resistivity of potassium and lithium both for the pure metals and some dilute alloys are presented using the forms for the energy dependence of the trial function obtained by Klemens (1954) as well as an approximation to it recently suggested by Ehrlich (1973). In addition, the function suggested by Ehrlich is slightly generalized and found to give better agreement with Klemens' form. In these calculations, realistic forms for the electron-phonon matrix elements are used and the effect of Umklapp processes is included. Also, the effect of anisotropy in the trial function is investigated in a simple approximation. For potassium, the latter effect is found to be negligible while for lithium it may be important. The deviations from Matthiessen's rule for the dilute potassium alloys are also calculated.