Photoelectron spectra of CeO- and Ce(OH)(2)(-)

摘要

The photoelectron spectrum of CeO- exhibits what appears to be a single predominant electronic transition over an energy range in which numerous close-lying electronic states of CeO neutral are well known. The photoelectron spectrum of Ce(OH)(2)(-), a molecule in which the Ce atom shares the same formal oxidation state as the Ce atom in CeO-, also exhibits what appears to be a single transition. From the spectra, the adiabatic electron affinities of CeO and Ce(OH)(2) are determined to be 0.936 +/- 0.007 eV and 0.69 +/- 0.03 eV, respectively. From the electron affinity of CeO, the CeO- bond dissociation energy was determined to be 7.7 eV, 0.5 eV lower than the neutral bond dissociation energy. The ground state orbital occupancies of both CeO- and Ce(OH)(2)(-) are calculated to have 4f 6s(2) Ce+ superconfigurations, with open-shell states having 4f 5d6s superconfiguration predicted to be over 1 eV higher in energy. Low-intensity transitions observed at higher electron binding energies in the spectrum of CeO- are tentatively assigned to the (1)Sigma(+) (Omega = 0) state of CeO with the Ce+2 6s(2) superconfiguration. (C) 2015 AIP Publishing LLC.