Hydration of Mg2+ and its influence on the water hydrogen bonding network via ab initio QMCF MD

An ab initio quantum mechanical charge field molecular dynamics (QMCF MD) simulation has been carried out in order to obtain detailed insight into the hydration properties of Mg2+. The ion, being a 'kosmotrope', considerably influences the water hydrogen bond network in its vicinity. Certain types of hydrogen bonds are strengthened at the cost of weakening others. The cationic influence on the water hydrogen bonding network have been investigated primarily employing time correlation functions of H-bond dynamics. The frequencies of the MgO6 skeletal normal modes calculated using the normal coordinate analysis shows a close resemblance to the experimental data, thus validating the accuracy of ab initio quantum chemical simulations. (C) 2012 Elsevier B. V. All rights reserved.