Identities for density functionals linking functionals of different densities
arXiv:1108.1094
Abstract
In electron density functional theory formal properties of density functionals play an important role in constructing and testing approximate functionals. In this paper it is shown that a set of density functionals satisfy an equation that links functionals of densities of N and N-1 systems of the same Hamiltonian. In particular the identity is satisfied by the sum of the Hartree and exchange-correlation energies.
13 pages