Doping Mechanisms in the Cuprate and Bismuthate Superconductors

The calculated band properties of the cuprate and bismuthate high-T sub c superconductors provide valuable insight regarding the chemistry and doping mechanisms that are operative in these compounds. In particular, these results distinguish chemical constituents that are electronically active from those which are not and suggest how substitutional doping can reduce below half the filling of the sigma-antibonding band ( or bands ) that are common to these materials.