On the mechanism of the reaction of CF3 radicals with C6F5Cl in the temperature range 318-473 K

Article abstract of DOI:10.1002/bbpc.19971010515

The gas-phase reaction of CF₃ radicals, generated by photolysis of perfluoroacetic anhydride, with C₆F₅Cl was studied in the temperature range 318-473 K and total pressures between 23 and 41 Torr. CF₃ radicals react with C₆F₅Cl according to the following mechanism: CF₃ + C₆F₅Cl ?^kadd CF₃C₆F₅Cl (1), (-1) CF₃ + CF₃C₆F₅Cl → CF₃Cl + C₆F₅CF₃ (2) 2CF₃ →^kc C₂F₆ (3) It was found that the addition reaction becomes reversible above 390 K. The addition rate parameters can be summarized in the following equation: log [(k_add/k_c^1/2)mol^-1/2cm ^3/2s^-1/2] = (4.46±0.10)-(22.48±0.70)/θ where θ = 2.303 RTkJ mol^-1 and k_c is the recombination constant of CF₃ radicals. A correlation between log(k_add/k_c^1/2) and the ionization potentials for 15 aromatic compounds was found. VCH Verlagsgesellschaft mbH, 1997.