Proof that ∂E∂ni=ɛ in density-functional theory
Abstract
It is shown that the variation of the total energy, as constructed in density-functional theory, with respect to an orbital occupation is equal to the eigenvalue of that orbital, independent of the detailed form of the exchange-correlation functional. This leads to a rigorous connection between the ground-state energies of N- and (N+1)-particle systems, which is useful in the calculation of certain excitation energies.
- Publication:
-
Physical Review B
- Pub Date:
- December 1978
- DOI:
- 10.1103/PhysRevB.18.7165
- Bibcode:
- 1978PhRvB..18.7165J