Density-functional formula for strongly correlated systems

Up to now, computation method dealing withthe many electron systems has been based on single particle approximation. That is to say, the wavefunctions of a system are composed of single particlewave functions (SPWF’s), and all the physical prop erties are determined by the SPWF’s. There havebeen two sophisticate techniques to solve the SPWF’s.One is the well known Hartree Fock self consistent e quations (HFSCE). The other is the Kohn Sham e quations of density funct…