Quantum chemical and electrostatic studies of anionic water clusters, (H<SUB>2</SUB>O)<SUB>n</SUB><SUP>-</SUP>

Quantum chemical investigations are carried out to determine the structure and energetics of anionic water clusters, (H2O)n- for n = 8, 10, 12 and 15. Quantum chemical computations performed herein employing a density functional theory (DFT) prescription reveal that these open-shell anionic clusters are metastable in comparison with their neutral analogues. Electron localization of the excess electron in these clusters, traced through molecular electrostatic potential (MESP) and singly occupied molecular orbital (SOMO) density maps, brings out the fact that the excess electron in these clusters is essentially a 'surface' electron i.e. binds externally to the cluster