Structural and Infra Red Spectroscopic Aspects of Ion-Water Clusters: A Study Based on a Combined Stochastic and Quantum Chemical Approach

Abstract

In the present communication, we explore a strategy based on using a stochastic technique, namely Simulated Annealing (SA), in conjunction with quantum chemical calculations to arrive at good candidate structures for ion-water clusters. We investigate if our approach is equally suited to handle structures in which the encapsulated ion is cationic (Na+) as well as anionic (Cl−). To critically analyse the quality of structure being generated, we perform spectroscopic and thermochemical studies on these systems and compare our results with the available experimental ones. We conclude that our idea is both computationally cost effective as well as quantitatively accurate in providing good quality structures for these systems. Structure of (H2O)6Na+ obtained after Simulated Annealing optimization (using an emperical potential) followed by further optimization at MP2 level of theory