Rate constants for the gas-phase reactions of hydroxyl radicals and chlorine atoms with aliphatic alcohols and ethers have been determined at 298 f 2 K and at a total pressure of 1 atmosphere. The OH radical rate data were obtained using both the absolute technique of pulse radiolysis combined with kinetic UV spectroscopy and a conventional photolytic relative rate method. The C1 atom rate constants were measured using only the relative rate method.

The reaction mechanisms for oxidation of CH,CCI, and CC13CH2 radicals, formed in the atmospheric degradation of CH3CC1, have been elucidated. The primary oxidation products from these radicals are CH,CClO and CCl,CHO, respectively. Absolute rate constants for the reaction of hydroxyl radicals with CH3CC13 have been measured in 1 atm of Argon at 359, 376, and 402 K using pulse radiolysis combined with UV kinetic spectroscopy giving k(OH + CHThe effect of chlorine substitution on the reactivity of organic compounds towards OH radicals is discussed.

The gas phase reaction of OH radicals with dimethyl sulfide (CH,SCH,, DMS) has been studied using both an absolute and a relative technique a t 295 2 2 K and a total pressure of 1 atm. The absolute rate technique of pulse radiolysis combined with kinetic spectroscopy was applied. Using this technique a rate constant of (3.5 t 0.2) x cm3 molecule-' sK1 was obtained. For the relative rate method, rate constants for the reaction of OH with DMS were found to increase with increasing concentrations of added NO. These results are compared with the large body of kinetic and mechanistic data previously reported in the literature.

Rate constants for the reactions of OH radicals and C1 atoms with diethyl sulfide (DES), din-propyl sulfide (DPS), and di-n-butyl sulfide (DBS) have been determined at 295 ? 3 K and a total pressure of 1 atm. Hydroxyl radical rate data was obtained using the absolute technique of pulse radiolysis combined with kinetic spectroscopy. The chlorine atom rate constants were measured using a conventional photolytic relative rate method. The rate constant for the reaction of C1 atoms with dimethyl sulfide (DMS) was also determined. The following rate constants were obtained:k(C1 + DES) = (44.1 5 4) X 1 0 . ' ' cm3 molecule-'s-' k(C1 + DPS) = (51.8 5 41 x lo-" cm3 molecuIe-'s-' k(C1 + DBS) = (64.6 5 2) X lo-" cm3 molecule-' s-l

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