Thomson Effect in Zinc Crystals

Abstract

The Thomson coefficient, $\sigma$, is directly determined for a group of zinc crystal rods with orientations distributed fairly uniformly over the entire possible range. At 49.5°C and at 125°C the values of $\sigma$ seem to obey the Voigt-Thomson symmetry relation, although not as good a check is obtained at the higher temperature on account of increased experimental error. The principal values obtained are: $\{\mathrm{At} 49.5°\mathrm{C}, {\sigma }_{\perp },=0.98\mathrm{}\times {10}^{-6\mathrm{}}\mathrm{cal}.\mathrm{}{\mathrm{coul}.\mathrm{}}^{-1\mathrm{}}{\mathrm{deg}}^{-1\mathrm{}}\}\{{\sigma }_{\parallel }=0.38\mathrm{}\times {10}^{-6\mathrm{}}\}\{\mathrm{At} 125°\mathrm{C}, {\sigma }_{\perp },=2.09\mathrm{}\times {10}^{-6\mathrm{}}\}\{{\sigma }_{\parallel }=1.08\mathrm{}\times {10}^{-6\mathrm{}}\}$