Development of the ColleSalvetti correlationenergy formula into a functional of the electron density
Abstract
A correlationenergy 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 secondorder HartreeFock density matrix, is restated as a formula involving the density and local kineticenergy density. On insertion of gradient expansions for the local kineticenergy density, densityfunctional 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 closedshell type, it is demonstrated that these formulas, like the original ColleSalvetti 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