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The reaction of dimethyl ether (DME) with OH radical was studied using a laser photolysis-laser induced fluorescence technique in the temperature range of 257–333 K at 30 Torr. The temperature dependent rate coefficient is represented by the expression, k T = 9.7 ± 1.0 × 10 - 12 exp - 380 ± 25 / T c m 3 m o l e c u l e s - 1 s - 1 and atmospheric lifetime was found to be 4.7 days. To elucidate the reaction mechanism and complement the experimental work, the energies and structures of the reactants and transition states involved were determined theoretically using the G3 method. The radiative forcing and the global warming potential for 100 years time horizon of DME were estimated to be 0.03 W m−2 ppb−1 and 0.02, respectively.

The rate coefficients for reactions of 1-chlorocyclopentene with OH have been measured in the temperature range of 262–335 K, at total pressure of 30 Torr, using Laser Photolysis-Laser Induced Fluorescence. The rate coefficient can be expressed as k(T)=(6.32 ± 1.16) × 10-12 exp((669 ± 45)/T) cm3molecules-1s−1, and thus it depends weakly on temperature. It decreases with increasing temperature, which was attributed to formation of a pre-reactive complex between reactants. Molecular orbital calculations confirm participation of such a complex during an addition reaction, and also predict several other hydrogen abstraction pathways. The studies suggest the dominance of addition reaction over H atom abstraction in the reaction of 1-chlorocyclopentene with OH.