Structure and dynamics of the UO2+ ion in aqueous solution: an ab initio QMCF-MD study.

ABSTRACT

The quantum mechanical charge field molecular dynamics (QMCF-MD) framework was applied in a simulation of the uranyl(v) ion in aqueous solution. The structure was evaluated on the basis of overall and sectorial radial distribution functions, angular distribution functions, tilt- and Theta-angle distribution functions and coordination number distributions. The cation is strongly coordinated by 4 water ligands at an average distance of 2.51 A, while the oxygen atoms are on average bound to 1.2 water molecules at a distance of 2.9 A. A mean residence time of 2.83 ps was evaluated for the oxygen sites of the uranyl(v) ion. The results are in good agreement with previous experimental and theoretical data on the hydration of similar ions.