The rates for production of the compounds S
2F
10, S
2OF
10, and S
2O
2F
10 have been measured both in spark and continuous, constant-current negative glow corona discharges generated using point-to-plane electrode gaps in 'pure'SF
6 and SF
6/O
2 gas mixtures containing up to 10% oxygen by volume fraction. In the case of corona discharges in pure SF
6, the S
2F
10 concentrations were measured as a function of time during discharge operation using a gas chromatograph-mass spectrometer for gas pressures in the range of 100kPa to 500kPa and at discharge currents between 2μA and 80μA. The charge rate-of-production of S
2F
10 from negative corona is observed to drop with decreasing discharge current, and the yield curves exhibit nonlinearities in the early stages of the discharge associated with "conditioning" of the point electrode. The initial nonlinearities become more pronounced with increasing gas pressure. The absolute yields of S
2OF
10 and S
2O
2F
10 were measured as a function of O
2 content in SF
6 for both negative glow corona (40μA and 200kPa) and spark discharge (80J/spark and 100kPa). The gas analysis in the case of spark discharges was performed after each spark using a cryogenic enrichment chromatographic technique. When O
2 is added to the gas, there is a dramatic drop in the S
2F
10 yield from both types of discharges with a corresponding increase in S
2OF
10 yield from the spark and S
2O
2F
10 yield from the corona discharge. The results can be explained within the framework of a plasma-chemical model from considerations of the competition among the reactions of SF
5 radicals produced by dissociation of SF
6 in the discharge with SF
5 itself as well as with O
2 and O, and the relative degree of O
2 dissociation in the two types of discharges.
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