Resistivity of Very Pure Th and Th—Rare-Earth Alloys

Abstract
Resistivity data are given for pure thorium samples with a resistivity ratio [Γ=ρ300Kρ4.2K] greater than 1000. At high temperatures, deviations of the resistivity from the Block-Grüneisen relation correspond closely to the anomaly which is found in the specific heat. The resistivity at 300°K is found to be 15.8 μΩ-cm. Thorium—rare-earth alloys show no resistance minimum of the type discussed by Kondo, to an accuracy of 0.001 μΩ cm.