Reactivity of hydrohaloethers with OH radicals and chlorine atoms: Correlation with molecular properties

The reactivity of halogenated ethers, especially hydrochloroethers, with hydroxyl radicals and chlorine atoms was studied by correlating the room-temperature rate coefficients with both the C H bond dissociation energies and the vertical ionization potentials of the parent molecules. These molecular properties were estimated at the composite G3B3 level of theory. The results suggest that Cl-substituted ethyl-methyl-ethers and ethyl-ethyl-ethers at the beta-position tend to raise the activating effect of the ether linkage 0 and to enhance the possibility of the abstraction of H atoms bonded to a-carbon. Derived relationships between the rate coefficients (in cm(3) molecule(-1) s(-1)) and ionization potentials (in eV): log k(OH) = (1.248 0.065) IP + (1.06 0.73) and log k = (1.46 0.12) IF + (4.5 1.3) allows, in average, to estimate rate coefficients within a factor of 2-3. The atmospheric implications of halogenated and hydrogenated ethers are briefly discussed on the basis of their estimated global lifetimes. (C) 2014 Elsevier Ltd. All rights reserved.