The Hall coefficient of a number of samples of $\beta -{\mathrm{Ag}}_2\mathrm{Te}$ has been measured as a function of temperature from 80 to 373°K. The polycrystalline ingots were prepared by direct reaction of the elements either in vacuum or in oxygen gas. Data on seven $p$-type samples prepared from five different ingots have been analyzed in terms of an 0°K energy gap $E_0=(0.064\mathrm{}\pm 0.009)$ eV including a correction for the effect of degeneracy.

• Received 4 October 1965

DOI:https://doi.org/10.1103/PhysRev.143.666