Abstract
We analyze the experimental core-level photoemission and x-ray absorption (XA) spectra of in terms of an Anderson-impurity Hamiltonian including the band-structure effects of the oxygen sublattice and show that the XA results unambiguously indicate a negative value of the charge-transfer energy Δ. We also perform mean-field calculations for the electronic structure for the edge-shared one-dimensional lattice of within the multiband Hubbard Hamiltonian and show that the origin of the insulating nature lies in band-structure rather than correlation effects, and that the gap has a pd-p character.
- Received 16 November 1992
DOI:https://doi.org/10.1103/PhysRevB.47.10927
©1993 American Physical Society