Reactions of methyl and ethyl radicals with uranium hexafluoride

We have measured the rates of reaction of both methyl and ethyl radicals with uranium hexafluoride (UF6) in the gas phase. The method we used was to photolyze samples of UF6 in the presence of either methane or ethane. The radicals produced by reaction of fluorine atoms with these species then react with either themselves or with UF6. We inferred the rate constants from ratios of the reaction products and the published rate constants for radical recombination. The diagnostic technique was gas chromatography. The resulting rate constants for reaction with UF6 were (1.6±0.8)×10−14 cm3 molecule−1 s−1 for methyl radicals and (4±2)×10−11 cm3 molecule−1 s−1 for ethyl radicals.