Infrared Absorption Spectra of SSO- Anion in Solid Argon

Abstract

When a high-frequency discharged CS2:O2:Ar sample was condensed at 4 K, new absorptions at 1003.1 and 567.7 cm-1 were produced. Isotopic substitution (13CS2/O2, C34S2/O2, CS2/18O2, and mixtures) shows that these new absorptions are due to S−O and S−S stretching vibrations, which involve two inequivalent S atoms and one O atom. The photosensitive behavior and the agreement with frequencies and isotopic frequency ratios from quantum chemical calculations substantiate assignment of these absorptions to the SSO- anion, which was predicted to have a bent structure with elongated S−S and S−O bond lengths relative to those of S2O.