Conductivity and Hall effect have been measured in the intrinsic range of germanium from 250° to 1000°K. From lattice-scattering mobility and conductivity below 500°K, a new empirical expression for carrier concentration is determined: $np=3.10\mathrm{}\times {10}^{32}{T}^3\exp (-\frac{0.785}{\mathrm{kT}})$. An estimate is made of the contribution of optical modes to the lattice-scattering mobility. Conductivity from 500° to 1000° and Hall effect from 250° to 1000° are computed and compared with experiment. Included in the computation are: the empirical expression for carrier concentration modified by the change in intrinsic ionization energy produced by electrostatic interaction of charge carriers, extrapolated empirical lattice scattering mobility, scattering by electron-hole collisions, and an extrapolation of the ratio Hall mobility/conductivity mobility.

• Received 4 February 1954

DOI:https://doi.org/10.1103/PhysRev.94.1525