Thermoelectric power of alloys: Validity of the gorter-nordheim relation

Abstract

The influence of impurities on the diffusion thermoelectric power of a metal is generally discussed in terms of the Friodel or the Gorter-Nordheim relation. We consider the validity criteria for the Gorter-Xordheim relation (which is equivalent to Friedel's) and show that its range of applicability may extend to impurity concentrations where Matthiessen's rule is violated. Moreover, the impurity concentration at which substantial departures from the Gorter-Nordheim relation occur appears to be indicative of the onset of significant qualitative departures of the shape of the Fermi surface from that of the pure metal. Experimental data on several copper alloys provide reasonable support for our arguments and suggest that thermoelectric effects may yield interesting qualitative information on the band structure of concentrated alloys.