Density-Functional Theory of the Energy Gap

L. J. Sham; M. Schlüter

doi:10.1103/PhysRevLett.51.1888

Density-Functional Theory of the Energy Gap

L. J. Sham and M. Schlüter

Phys. Rev. Lett. 51, 1888 – Published 14 November 1983

Abstract

The energy-band gap of an insulator is obtained from the eigenvalues of the one-particle density-functional equation for the ground state and a finite correction due to the discontinuity of the functional derivative of the exchange and correlation energy. This correction is expressed in terms of the improper self-energy and the density-functional exchange-correlation potential. It is evaluated for a two-plane-wave model including exchange only.

Received 23 June 1983

DOI:https://doi.org/10.1103/PhysRevLett.51.1888

Authors & Affiliations

L. J. Sham^*

Department of Physics, University of California San Diego, La Jolla, California 92093, and Institute for Theoretical Physics, University of California Santa Barbara, California 93106

M. Schlüter