UV-vis spectral properties of I-2(center dot-)center dot nH(2)O systems are reported based on A initio quantum chemical calculations. Second order Moller-Plesset perturbation theory is applied for geometry search and time dependent density functional theory is applied to study excited state properties. Relativistic corrections are considered for all the Calculations. Geometry search is carried Out applying simulated annealing combined with Monte Carlo sampling method. Strong optical absorption band of these hydrated clusters, I-2(center dot-)center dot nH(2)O in the UV-vis region is assigned to sigma(g) -> sigma(u)* type valence electron transition in contrast to charge transfer to solvent spectra in I-center dot nH(2)O systems. Simulated optical absorption profile of I-2(center dot-)center dot 8H(2)O system is in excellent agreement with the reported aqueous phase spectrum of iodine dimer radical anion.