Abstract
Electronic-structure calculations have been carried out for representative members of the alloy series with the use of the self-consistent, scalar-relativistic, linear augmented plane-wave (LAPW) method and the virtual-crystal approximation. The study includes LAPW calculations for the high-temperature cubic () as well as the room-temperature tetragonal () and monoclinic () phases. The cubic results exhibit nearly-rigid-band—like behavior and feature a ten-band complex near containing a pair of broad (∼16 eV) -bonding subbands that are approximately centered on nonbonding O states. band overlap and metallic properties are predicted for all in the cubic phase. The principal features of the cubic band structure survive the tetragonal distortion, predicting a nearly spherical Fermi surface and a low density of states at in the concentration range where high-temperature superconductivity ( K) is observed. A strong Fermi-surface instability is shown to occur in the terminal () BaBi compound, explaining both the stability of the monoclinic phase as well as its semiconducting properties.
- Received 13 April 1983
DOI:https://doi.org/10.1103/PhysRevB.28.4227
©1983 American Physical Society