Abstract
The production ofSOF 4 initiated by the reaction of F atoms withSOF 2 has been studied in a gas-flow reactor at 295 K for helium bath gas number densities in the range (3.0–27.0)×1016 cm−3. The effect of O atoms on the formation ofSOF 4 has been analyzed in terms of the competing reactionsSOF 3+F→SOF4 andSOF 3+O→SO 2 F 2+F. This analysis leads to the conclusion that the rate coefficients for these two processes are equal within an uncertainty of about 50%. Furthermore, both experiment and calculations indicate that the rate coefficient for reactions between F atoms andSOF 3 is close to its high-pressure limit under the conditions employed. The experiments set a lower limit on this rate coefficient of 5×10−11 cm3 s−1, while calculations based on unimolecular rate theory suggest that it may be greater than 1×10−10 cm3 s−1. These results make it clear that the two reactions shown above cannot explain the relative abundances ofSOF 4 andSO 2 F 2 which are observed inSF 6/O 2 plasmas. This suggests thatSF 2 is a major precursor in the sequence of reactions following the dissociation ofSF 6.
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Ryan, K.R. Aspects of the chemistry of SF6/O2 plasmas. Plasma Chem Plasma Process 9, 483–496 (1989). https://doi.org/10.1007/BF01023915
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DOI: https://doi.org/10.1007/BF01023915