| Abstract
| - The absolute rate constants for the reactions of chlorine atoms with a series of fluorinated ethanols CF3CH2OH (1), CHF2CH2OH (2), and CH2FCH2OH (3) were measured in the gas phase over the temperature range273−363 K, by employing the discharge-flow mass spectrometric technique with a Knudsen type reactor.The absolute rate constants are given by the following expressions (in cm3 molecule-1 s-1, 2σ uncertainties): k1 = (0.85 ± 0.19) × 10-11 exp((−792 ± 74)/T), k2 = (2.61 ± 0.49) × 10-11 exp((−662 ± 60)/T), and k3= (7.57 ± 0.98) × 10-11 exp((−408 ± 40)/T). The title reactions take place primarily via the abstraction ofmethylene hydrogen, yielding the corresponding fluoroethanol radicals, which subsequently may undergooxidation reactions, resulting in fluoroacetaldehydes. Quantum mechanical calculations of the C−H bondenergies in the title alcohols at the B3P86/6-311++G(2df,p) level of theory show that the methylene hydrogenbonds are the weakest. The atmospheric degradation mechanism of the title fluorinated ethanols is alsopresented.
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