The dynamics of the solvation of Pb(II) in aqueous solution obtained by an ab initio QM/MM MD approach

Dynamic properties of the hydrated Pb(II) ion have been investigated by ab initio quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) simulations at Hartree Fock quantum mechanical level. Librational as well as vibrational motions of first and second shell and the bulk as well as the frequencies of rotations have been evaluated by means of velocity auto correlation functions (VACF). The time evolution of the Pb-O distances and selected O-Pb-O angles in the first shell was evaluated. A lower limit of the mean ligand residence time of water molecules in the first shell was estimated as 0.23 ns, in the second shell a mean residence time of 5.6 ps was observed. (c) 2005 Elsevier B.V. All rights reserved.