ABEEM/MM-BASED PAIR POTENTIAL FOR MOLECULAR DYNAMICS SIMULATION OF Fe2+(aq) AND Fe3+(aq)

Abstract

On the basis of atom-bond electronegativity equalization method fused into molecular mechanics (ABEEM/MM), we have constructed the effective Fe 2+ and Fe 3+ ion-water potential by fitting to ab initio structures and binding energies for ionic clusters, where Fe 2+ and Fe 3+ ions are in their high spin state. We then apply the ion-water interaction potential in combination with the ABEEM-7P water model to molecular dynamic simulations of single-ion Fe 2+( aq ) and Fe 3+( aq ) solutions, managing to reproduce many experimental, structural and dynamical properties of the solutions. The effects of ionic charges on structural and dynamical properties of water molecules in the hydration shells are discussed.