Binding properties of 3d transition metals in a generalized density-functional theory

In a preceding paper we have reported on band-gap corrections in semiconductors and insulators that were calculated within a generalized density-functional (GDF) theory. Similar to an earlier idea of Gunnarsson and Jones, we describe exchange and correlation effects by suitably modeled pair-correlation factors. They are subject to certain sum rules that ensure the absence of self-interaction in the electron-electron interaction integrals. The resulting exchange-correlation potential in the GDF-derived one-particle equations is «nonlocal» (NL), as distinct from its local-density approximation (LDA) analogue, which has so far almost exclusively been used in performing DF calculations on solids.