Microsolvation of the Zn(II) ion in aqueous solution: A hybrid QM/MM MD approach using non-periodic boundary conditions

A novel molecular dynamics methodology, which is based on an integrated ab initio/classical potential using localized basis functions and non-periodic boundary conditions, has been applied to study the microsolvation of the Zn(II) ion in aqueous solution. The metal ion, along with its first solvent shell, was treated at DFT B3LYP level, while the remaining bulk solvent was modeled with an effective TIP3P water model. The solvent structural arrangement around the ion has been analyzed and the characteristic Zn–O distance favourably compared to recent ND, XRD and EXAFS experiments, as well as to sophisticated cluster calculations.