The mechanism of water exchange in AmO2(H2O)5(2+) and in the isoelectronic UO2(H2O)5(+) and NpO2(H2O)5(2+) complexes as studied by quantum chemical methods

Valérie Vallet; Timofei Privalov; Ulf Wahlgren; Ingmar Grenthe

doi:10.1021/ja0483544

The mechanism of water exchange in AmO2(H2O)5(2+) and in the isoelectronic UO2(H2O)5(+) and NpO2(H2O)5(2+) complexes as studied by quantum chemical methods

J Am Chem Soc. 2004 Jun 30;126(25):7766-7. doi: 10.1021/ja0483544.

Authors

Valérie Vallet¹, Timofei Privalov, Ulf Wahlgren, Ingmar Grenthe

Affiliation

¹ Technical University of Munich, D-85747 Garching, Germany. [email protected]

PMID: 15212510
DOI: 10.1021/ja0483544

Abstract

The water exchange mechanism for AmO2(H2O)52+ and the isoelectronic UO2(H2O)5+ and NpO2(H2O)52+ ions has been investigated using quantum chemical methods and compared to previous findings in the uranyl(VI) system (Vallet, V. et al. J. Am. Chem. Soc. 2001, 123, 11999). There are substantial and predictable changes in the geometry and preferred exchange pathways between uranyl(V) and the different actinyl(VI) complexes. The smaller charge on the uranyl(V) center makes the dissociative pathway more favorable than the associative/interchange pathways in the actinyl(VI) systems.