Hyperfine interactions in iron substituted high-Tc superconducting oxides

The hyperfine interactions in Fe substituted copper oxide ternary and quaternary compounds with perovskite-related structures are studied, using the local density theory in an embedded cluster approach. The self-consistent electronic structure is examined for Cu and Fe sites in a number of plausible local geometries representative of La2CuO4, YBa2Cu3O7-δ and related materials. Moessbauer isomer shifts, electric field gradients, magnetic moments and contact hyperfine fields are presented for comparison with experiment and discussed in light of lattice structure data. (orig.)