Communication: Kohn-Sham theory for excited states of Coulomb systems

For obtaining individual excited-state energies and densities of Coulomb electronic systems, by means of an energy stationary principle, it was shown previously that there exists a universal functional of the density, FCoul[ϱ], for the kinetic plus electron-electron repulsion part of the total energy. Here, we make knowledge of the existence of FCoul[ϱ] practical for calculation by identifying TsCoul[ϱ], the non-interacting kinetic energy component of FCoul[ϱ], and by showing that TsCoul[ϱ] may be computed exactly by means of orbitals that are obtained through a set of single-particle Kohn-Sham equations. Constraints for obtaining accurate approximations to the remaining unknown component of FCoul[ϱ] are presented.

Communication: Kohn-Sham theory for excited states of Coulomb systems Journal Articles