Density-functional theory of the band gap
Abstract
There is a correction to the energy band gap obtained from the eigenvalues of the exact one-electron density-functional equation due to the discontinuity in the exchange-correlation potential in an insulator. This correction is expressed in terms of the electron self-energy. If the local-density approximation is used for the exchange-correlation potential, then an additional correction to the gap is needed. Both terms are evaluated for a two-plane-wave model with exchange only. Empirical evidence is also given for the discontinuity.
- Publication:
-
Physical Review B
- Pub Date:
- September 1985
- DOI:
- 10.1103/PhysRevB.32.3883
- Bibcode:
- 1985PhRvB..32.3883S
- Keywords:
-
- 71.45.Gm;
- 71.25.Rk;
- 71.25.Cx;
- Exchange correlation dielectric and magnetic response functions plasmons