Molecular exchange-correlation Kohn–Sham potential and energy density from ab initio first- and second-order density matrices: Examples for XH (X=Li, B, F)

Abstract

The molecular Kohn–Sham exchange‐correlation potential v xc and the energy density εxc have been constructed from ab initio first‐ and second‐order density matrices for the series XH (X=Li, B, F). The way various effects of electronic structure and electron correlation manifest themselves in the shape of v xc and εxc has been analyzed by their decomposition into various components; the potential of the exchange‐correlation hole, the kinetic component and (in the case of v xc) the ‘‘response’’ component. The kinetic energy of noninteracting particles T s , the kinetic part of the exchange‐correlation energy T c , and the energy of the highest occupied molecular orbital ε N have been obtained with reasonable accuracy and the effect of bond formation on these functionals has been studied.