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
©1983 American Physical Society