ENERGY-BANDS AND EFFECTIVE MASSES OF CUCL

We have made the first self-consistent energy-band calculation of CuCl with sufficient variational freedom to calculate the effective masses accurately. The conduction-band mass agrees with experiment whereas the valence-band mass is much less than any of the experimental values, indicating that the hole forms a small polaron. The calculation was repeated for a reduced lattice constant. The indirect gap proposed by Rusakov to explain the high-temperature superconductivity" anomaly does not exist and the direct gap widens with pressure. © 1979 The American Physical Society."