Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density
Abstract
A correlation-energy formula due to Colle and Salvetti [Theor. Chim. Acta 37, 329 (1975)], in which the correlation energy density is expressed in terms of the electron density and a Laplacian of the second-order Hartree-Fock density matrix, is restated as a formula involving the density and local kinetic-energy density. On insertion of gradient expansions for the local kinetic-energy density, density-functional formulas for the correlation energy and correlation potential are then obtained. Through numerical calculations on a number of atoms, positive ions, and molecules, of both open- and closed-shell type, it is demonstrated that these formulas, like the original Colle-Salvetti formulas, give correlation energies within a few percent.
- Publication:
-
Physical Review B
- Pub Date:
- January 1988
- DOI:
- 10.1103/PhysRevB.37.785
- Bibcode:
- 1988PhRvB..37..785L
- Keywords:
-
- 31.20.Tz;
- 31.20.Lr;
- 31.15.+q;
- 71.10.+x