Raman Spectroscopic Study of a New Type of Room Temperature ZnCl2-DMSO2 Molten Salts

In this study, Raman spectra of binary zinc chloride-dimethylsulfone (ZnCl{sub 2}-DMSO{sub 2}) melts have been measured. The intra-molecular vibrations of group and ionic species have been confirmed and discussed. From the Raman spectrum analysis and discussions, the equilibrium reaction equation about the complex ions forming in the ZnCl{sub 2}-DMSO{sub 2} melt is submitted, such as nZnCl{sub 2} + n(n - 2)(CH{sub 3}){sub 2}SO{sub 2} 2ZnCl{sub n}{sup 2-n} + (n - 2) Zn[(CH{sub 3}){sub 2}SO{sub 2}]{sub n}{sup 2+}, (n {>=} 3). However, the Raman spectra reveal that the ZnCl{sub 4}{sup 2-} (375 cm{sup -1}) and ZnCl{sub 3}{sup -} (290 cm{sup -1}) complexes are the major ions for the 40 - 90 mol% ZnCl{sub 2} melts; furthermore, as the DMSO{sub 2} content is increased, the binary melt advantage the forming of Zn[(CH{sub 3}){sub 2}SO{sub 2}]{sub n}{sup 2+} complex ion and promote its transport characteristic. (orig.)