INFLUENCE OF CORE-VALENCE SEPARATION OF ELECTRON LOCALIZATION FUNCTION

The electron localization function (ELF) shows too-high values when co mputed from valence densities only (instead of using the total density ). This effect is mainly found when ci electrons are present in the ou termost shell of the core. Although no pronounced qualitative differen ces could be noticed in the examples studied up to now, it is found th at the quantitative differences between the values of ELF obtained fro m the valence densities only or from the total densities can be large. We also show, for the first time, an example (the Be atom) where ELF is obtained directly from the density. This exemplifies the possibilit y of computing ELF from highly accurate calculations (or from experime ntal data). (C) 1997 John Wiley & Sons, Inc.