Properties and nature of interactions in Cl-(H2O)(n) n=1,6 clusters: a theoretical study

A series of Cl-(H2O)(n) complexes has been studied using ab initio post-Har tree-Fock methods. The arrangement of water molecules around the chloride i on in the Cl-(H2O)(n) clusters reveals the competition between the solvatio n of an anion and the hydrogen bonding between solvent molecules. The large r studied clusters (n = 5,6) possess water molecules in the second solvatio n shell. Experimental electron affinities together with experimental dissoc iation energies of ionic clusters were used to estimate the properties of n eutral Cl(H2O)(n) complexes. The partitioning of the interaction energies i n ionic Cl-(H2O)(n) clusters indicates the dominant character of the electr ostatic forces. (C) 2000 Elsevier Science B.V. All rights reserved.