title: Kohn-Sham theory for ground-state ensembles.
abstract: An electron density distribution n(r) which can be represented by that of a single-determinant ground state of noninteracting electrons in an external potential v(r) is called pure-state v-representable (P-VR). Most physical electronic systems are P-VR. Systems which require a weighted sum of several such determinants to represent their density are called ensemble v-representable (E-VR). This paper develops formal Kohn-Sham equations for E-VR physical systems, using the appropriate coupling constant integration. It also derives local density- and generalized gradient approximations, and conditions and corrections specific to ensembles.
authors.affiliation: iQUEST, University of California, Santa Barbara, 93106, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Ullrich
authors.forename: W
authors.initials: W
authors.lastname: Kohn