Abstract
Photoemission and bremsstrahlung-isochromat-spectroscopy data on a cleaved NiO single crystal are presented and compared to band- and cluster-theory predictions. In contrast to band-theory predictions the band gap is found to be large but not determined solely by the even larger Coulomb interactions so that NiO is not a Mott-Hubbard insulator in the simplest sense. A large interaction need not prevent NiS from being a metal.
- Received 5 July 1984
DOI:https://doi.org/10.1103/PhysRevLett.53.2339
©1984 American Physical Society