title: Covalency hinders AnO2(H2O)(+)→ AnO(OH)2(+) isomerisation (An = Pa-Pu).
abstract: The enthalpies of the reactions AnO2(+)→ AnO(+) + O and AnO2(+) + H2O → AnO2(H2O)(+), and those of the isomerisation of the latter to AnO(OH)2(+), have been calculated for An = Pa-Pu. The data match previous experimental and computational values very closely, and the computed enthalpy for the isomerisation of PaO2(H2O)(+) to PaO(OH)2(+), requested by the authors of Inorg. Chem., 2015, 54, 7474, is found to be 0.8 kJ mol(-1). The NPA, NBO and QTAIM approaches are used to probe covalency in the An-Oyl bond of AnO2(H2O)(+), and all metrics agree that these bonds become increasingly covalent as the 5f series is crossed, providing rationalisation for the increasingly endothermic isomerisation reactions. QTAIM analysis indicates that the An=O and An-OH bonds in the oxide hydroxide isomers also become increasingly covalent as the 5f series is crossed.
authors.affiliation: School of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK. nikolas.kaltsoyannis@manchester.ac.uk.
authors.forename: Nikolas
authors.initials: N
authors.lastname: Kaltsoyannis