CHEM01200604005 A. K. Pathak - Homi Bhabha National Institute

ulk water and pure neutral water clusters have been studied extensively, water
containing impurity molecules or ions (hetero clusters) is an equally important topic. 20 It
is difficult to get pure water naturally, as always other substances are dissolved in it.
Large number of atmospheric processes is believed to occur on water cluster and aerosol
surface, but not to occur in the gas phase. One of the major sources of halogens, i. e.
chlorine and bromine, in the atmosphere is also believed to be surface oxidation of
marine aerosols and clusters of seawater. 20 Studies on hetero clusters also provide a
convenient way to investigate atmospheric chemistry problems, e. g. ozone depletion.
The water clusters can also “dissolve” numerous organic compounds and can be used as a
medium for studies of aqueous organic reactions. 20 So microhydration of a solute is the
most common and popular research area for the past few years. Other well known solvent
having hydrogen bonded network is ammonia. Hydrogen bonded water network gets
rearranges in order to solvate the solute during the process of microsolvation. The
clusters of alkali metal atom and polar solvent molecules are studied at length, often from
interests related to the solvated electron. Solvated electrons can form rather readily with
the alkali metals because of the relatively low energy requirement for ionization.
However, the detailed mechanism on the formation of the solvated electron in this
medium with the alkali metal atom is not yet fully understood. Thus, solvated electron in
polar solvents has been a subject of continued research. Studies on microsolvation of
small chromophore are also carried out in non-polar and non-hydrogen bonded solvent
medium like carbon dioxide, argon, etc. As carbon dioxide is a weakly interacting
solvent, studies in this medium should help one to understand the dissociation and
recombination dynamics in order to model complex chemical reactions. Many
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