MOLECULAR KOHN-SHAM EXCHANGE-CORRELATION POTENTIAL FROM THE CORRELATED AB-INITIO ELECTRON-DENSITY

The molecular Kohn-Sham (KS) exchange-correlation potential nu(xc), ha s been constructed for LiH from the correlated ab initio density p by means of the simple iterative procedure developed by van Leeuwen and B aerends [Phys. Rev. A 49, 2421 (1994)]. The corresponding KS energy ch aracteristics, such as the kinetic energy of noninteracting particles T-s, kinetic part of the exchange-correlation energy T-c, and energy o f the highest occupied molecular orbital epsilon(N), have been obtaine d with reasonable accuracy. A relation between the form of nu(xc), and the electronic structure of LiH has been discussed. Test calculations for the two-electron H-2 molecule have shown the efficiency of the pr ocedure.