Electrical Properties of Nonstoichiometric Thorium Carbides

Abstract

The resistivity, Hall coefficient, and thermoelectric power of ThC_x, with x varying from 0.787 to 0.91, were measured from 4.2° to about 400°K. The results were analyzed in terms of a two‐band conductivity model. The analysis showed that as carbon is removed from the structure, band overlap increases and the number of carriers is increased. The resistivity data were analyzed using Matthiessen's rule and the analysis indicated that the residual resistivity arises from carbon vacancies. The vacancy contribution to the resistivity increases with increasing vacancy concentration.