Abstract
Electronic structures of electron-doped and have been investigated within the ab initio band-structure approach using a supercell containing eight basic units. A small amount of electron doping is found to drive metallic, with the Fermi level moving into the conduction band in both the systems. Clustering of oxygen vacancies in the case of gives rise to distinct non-rigid-band-like evolution of the electronic structure, trapping doped charge carriers in midgap states; similar effects are not observed for , explaining the difference in the Hall measurements of these two closely related compounds.
- Received 13 June 1997
DOI:https://doi.org/10.1103/PhysRevB.57.2153
©1998 American Physical Society