Electronic band structure of CaBi2Sr2Cu2O8

The band structure for body-centered tetragonal CaBi2Sr2Cu2O8 has been calculated in the local-density--functional approach by the linearized muffin-tin--orbital method with the atomic-sphere approximation. This is the undistorted, stoichiometric parent compound to the recently reported 84-K superconductor. The main band features at the Fermi level include a pair of nearly half-filled two-dimensional Cu-O 3d-2p bands similar to those found in the previous Cu-O planar superconductors as well as a pair of slightly filled Bi 6p bands that provide additional carriers in the Bi-O planes