title: A theoretical study of the ground state and lowest excited states of PuO0/+/+2 and PuO(2)0/+/+2.
abstract: The ground and excited states of neutral and cationic PuO and PuO2 have been studied with multiconfigurational quantum chemical methods followed by second order perturbation theory, the CASSCF/CASPT2 method. Scalar relativistic effects and spin-orbit coupling have been included in the treatment. As literature values for the ionization energy of PuO2 are in the wide range of approximately 6.6 eV to approximately 10.1 eV, a central goal of the computations was to resolve these discrepancies; the theoretical results indicate that the ionization energy is near the lower end of this range. The calculated ionization energies for PuO, PuO+ and PuO2+ are in good agreement with the experimental values.
authors.affiliation: Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, CH-1211, Geneva, Switzerland.
authors.forename: Giovanni
authors.initials: G
authors.lastname: La Macchia
authors.forename: Ivan
authors.initials: I
authors.lastname: Infante
authors.forename: Juraj
authors.initials: J
authors.lastname: Raab
authors.forename: John K
authors.initials: JK
authors.lastname: Gibson
authors.forename: Laura
authors.initials: L
authors.lastname: Gagliardi