Lattice Conductivity of Tin

The thermal conductivities of several impure tin specimens have been measured at liquid helium temperatures. Impurities of antimony, bismuth, and indium between 0.1% and 6% were used to lower the electronic conductivity. The conductivities are found to be consistent with the equation $K=\alpha T+\beta T^2$, where the first term may be ascribed to the electronic conductivity and the second to the lattice conductivity. For impurities of 3% or less the values of $\alpha$, combined with measurements of the residual electrical resistivity, agree to about one percent with the prediction of the Wiedemann-Franz law. For the same samples $\beta$ is approximately constant with a mean value of (3.5±0.4)×${10}^{-4\mathrm{}}$ watt/cm ${\mathrm{deg}}^3$. The comparative constancy of this value of $\beta$ indicates that it is characteristic of the intrinsic conductivity of the tin lattice.