MATRIX REACTIONS OF SULFUR-ATOMS AND FLUORINE - INFRARED-SPECTRA OF SF, SF2, AND SF3 IN SOLID ARGON

Sulfur vapor diluted with argon was passed through a microwave discharge and codeposited with argon-fluorine samples onto a CsI window at 12 K. Variation of fluorine and sulfur concentrations over a wide range and sulfur-34 isotopic substitution provided a basis for identification of the SF, SF2, and SF3 transient species. The diatomic SF radical showed matrix site absorptions at 818.8 and 822.0 cm-1 for (SF)S-34-F-19. A similar site splitting was also observed for both symmetric and antisymmetric stretching vibrations of SF2 at 832.5, 829.5 and 805.0, 804.6, 802.1 cm-1, respectively. The SF3 radical revealed symmetric equatorial and antisymmetric axial stretching vibrations at 843.8 and 681.8 cm-1, respectively. Sample annealing increased weak absorptions due to the higher fluoride species in the series including SF4 and SF6. Ab initio quantum chemical calculations verified these assignments.