THE EXPANSION OF THE HARTREE-FOCK APPROXIMATION BY A CORRELATION FUNCTION

Felix M. H. Villars

S. Boffi

N. Bjoernaa

V. Roerich, M. G. Gladush

Michele Fabrizio

Pan Zhang

The occupation renormalized Hartree-Fock single particle potential is extended to include the 'particle' state occupation. The exact solution, the solution of the occupation renormalized Hartree-Fock approximation and that of the Hartree-Fock approximation are calculated in Lipkin Model. It turns out that the RHF solution is more close to the exact one than the HF solution. The effect of occupation probability depends on the strength of the interaction of the two body term.