01-03E

Using the technique of molecular dynamics we made the attempt to clarify the effects of the presence of highly charged cations on the structure and dynamics of the water molecules in aqueous solution. Special attention is paid to cation first hydration shell. Analysis of radial distribution functions and velocity autocorrelation functions is performed in detail. It is shown that the strong ion-water electrostatic interaction leads to the formation of stable cluster which consists of six oxygens octahedrally arranged around the cation. The increase of cation valency makes the water molecules in hydration shell to stretch and even loose protons. The formation of hydroxonium molecules and more complicated structures is discussed. The correspondent velocity autocorrelation functions are investigated: the appearance of new frequencies in libration spectra of cation and oxygens from hydration shell is observed.