Recent thermal decomposition studies of SF6have led to interest in its principal oxidation product, sulfuryl difluoride. In the present study the thermal stability of SO2F2at high temperatures has been investigated. Highly dilute SO2F2sngbnd;Ar mixtures (sim;thinsp;0.1percnt;) were shock heated in a conventional 1.5Prime; stainlesshyphen;steel shock tube. The SO2F2concentration was monitored as a function of time behind the incident shock wave by its infrared emission at11.7 mgr;utilizing a liquid helium cooled Cu:Ge detector. The initial pressure in the shock tube was varied from 30 to 600 torr and the temperature range covered was 1900ndash;2300deg;K. The monitored radiation was shown to be transparent over the range of densities employed. Effective firsthyphen;order rate constants were evaluated from the logarithmic initial slopes of the radiation decay curves. For the 30hyphen;torr data, a unimolecular rate constant fit to the data iskeffthinsp;equals;thinsp;2.1thinsp;times;thinsp;1011explpar;minus;thinsp;39 200thinsp;sol;thinsp;Trpar;secminus;1. The data are analyzed in the light of several modern unimolecular rate theories, yielding sim;thinsp;81 kcal as the endothermicity for the reaction SO2F2plus;Arrarr;SO2Fplus;Fplus;Ar.
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