Discontinuity of the Exchange Correlation Potential from a Density Functional Viewpoint.
Abstract
The calculation of energy gaps of insulators is an important theory objective. A commonly used method is density functional theory. Recently it was shown that an unexpected difficulty (discontinuity of the exchange correlation potential) arises. This paper makes a contribution towards the understanding of this problem. The discontinuity is expressed in terms of changes of the exchange correlation energy, E sub xc, of a perfect N-particle insualtor when (a) a conduction electron is introduced (b) a valence electron is removed and (c) an external perturbation is applied to the perfect insulator (without changing N) such that the density change is equal to minus the sum of the density changes in (a) and (b).
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 10, 1986
- Accession Number
- ADA164377
Entities
People
- W. Kohn
Organizations
- University of California, Santa Barbara