CHEM01200604005 A. K. Pathak - Homi Bhabha National Institute

carbonate radical anion (CO 3 •− ), nitrate anion (NO 3
−
), and multiply charged anion e.g.
carbonate anion (CO 3 2− ) and halogen dimer (Cl 2 , Br 2 & I 2
) are taken to study
microhydration due to their chemical importance as well as progressive complexity.
Potassium atom and iodine dimer radical anion (I •− 2 ) are also taken to study the process
of microsolvation in ammonia and carbon dioxide solvents, respectively. Solubility, IR,
Photoelectron and UV-Vis spectral properties have also been predicted and compared
with experimental findings whenever available. When only one solvent molecule is added
to solvent, a few minimum energy structures are expected. With the increase in number
of solvent molecules in solvated clusters, the number of minimum energy configurations
with close in energy for each size solvated clusters are expected to increase. Experimental
observation on a particular size of cluster includes contribution from all possible
minimum energy structures, which survive at that particular condition of the experiment.
Average information is obtained from the experimental method. Thus weighted average
properties are calculated for better predictability. Fourier transform to the dipole and
velocity auto-correlation function is also done to include dynamical contribution to the
calculated IR spectra and compared to the weighted average IR spectra.
It is well known that bromine gas is more soluble than chlorine gas in water but
no theoretical understanding is available in the literature. UV-Vis spectra in aqueous
solution of Cl •− 2 , Br •− 2 , I •− 2 &, CO •− 3 radical anionic species, and specific one electron
oxidants are measured by experimental techniques. But theoretical attempt to generate
their absorption profiles is not available. A major part of the thesis (chapters 4, 5 & 8) is
dedicated to study bulk properties like solubility, aqueous UV-Vis spectra and bulk
detachment energy of excess electron. They are also systematically compared with
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