Rate constants and Arrhenius parameters for the reactions of Cl atoms with the halogenated ethers: CF3CH2OCHF2, CF3CHClOCHF2, and CF3CH2OCClF2

Rate constants have been determined for the reactions of Cl atoms with the halogenated ethers CF3CH2OCHF2, CF3CHClOCHF2, and CF3CH2OCClF2 using a relative-rate technique. Chlorine atoms were generated by continuous photolysis of Cl2 in a mixture containing the ether and CD4. Changes in the concentrations of these two species were measured via changes in their infrared absorption spectra observed with a Fourier transform infrared (FTIR) spectrometer. Relative-rate constants were converted to absolute values using the previously measured rate constants for the reaction, Cl + CD4 → DCl + CD3. Experiments were carried out at 295, 323, and 363 K, yielding the following Arrhenius expressions for the rate constants within this range of temperature:Cl + CF3CH2OCHF2: k = (5.15 ± 0.7) × 10−12 exp(−1830 ± 410 K/T) cm3 molecule−1 s−1Cl + CF3CHClOCHF2: k = (1.6 ± 0.2) × 10−11 exp(−2450 ± 250 K/T) cm3 molecule−1 s−1Cl + CF3CH2OCClF2: k = (9.6 ± 0.4) × 10−12 exp(−2390 ± 190 K/T) cm3 molecule−1 s−1The results are compared with those obtained previously for the reactions of Cl atoms with other halogenated methyl ethyl ethers.