Dynamics of ion solvation in binary solvent acrylonitrile/dimethyl sulfoxide

Raman spectra of solutions of lithium and sodium trifluoromethanesulfonates in the binary solvent acrylonitrile (AN)-dimethylsulfoxide have been considered. It was found that in the Li$^+$(AN)$_x$ and Na$^+$(AN)$_x$ solvatocomplexes the modulation times of the CN bond vibrations of acrylonitrile molecules $(\tau_\omega)$ are much larger than those for unbound acrylonitrile. Such a ratio between $\tau_\omega$ for bound and free molecules can be considered as a dynamic criterion for ion solvation in acrylonitrile solutions.