title: MRCI investigation of different isomers of Ni2O2H2(+).
abstract: The geometrical and electronic structures of different isomers of Ni(2)O(2)H(2)(+) are investigated by multireference configuration interaction (MRCI) calculations using natural atomic orbital basis sets. The lowest-lying isomer, Ni(2)(OH)(2)(+), has a rhombic shape with two OH groups bridging the Ni atoms. The next isomer in energetic order with a relative energy of 0.29 eV consists of a linear NiONi(OH(2))(+) chain. Other structures with a rhombic shape, (NiH)(2)O(2)(+), with H bound to the Ni atoms have considerably higher energies, above 4 eV. Especially the low-lying isomers are characterised by a large number of low-lying electronic terms. The product Ni(2)O(2)H(2)(+) of the reaction of Ni(2)O(2)(+) with small alkanes is likely to have the rhombic Ni(2)(OH)(2)(+) structure. The reaction energy of the reaction Ni(2)O(2)(+) + H(2)→ Ni(2)(OH)(2)(+) is estimated to be about -3.5 eV.
authors.affiliation: Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany. olaf.huebner@aci.uni-heidelberg.de
authors.forename: Olaf
authors.initials: O
authors.lastname: Hübner
authors.forename: Hans-Jörg
authors.initials: HJ
authors.lastname: Himmel