title: Lack of Hohenberg-Kohn theorem for excited states.
abstract: For a given excited state there exist densities that arise from more than one external potential. This is due to a qualitatively different energy-density relationship from that of the ground state and is related to positive eigenvalues in the nonlocal susceptibility for excited states. Resulting problems with the generalization of the density functional methodology to excited states are discussed.
authors.affiliation: Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Rd., Piscataway, New Jersey 08854, USA.
authors.forename: R
authors.initials: R
authors.lastname: Gaudoin
authors.forename: K
authors.initials: K
authors.lastname: Burke