THE ROLE OF CF3C(O)OX RADICALS IN ATMOSPHERIC CHEMICAL PROCESSES

Photo-oxidation of CF3CX2H (where X = H, F or Cl) alternative halocarbons leads to CF3C(O)X species whose further degradation is also initiated either by reaction with OH radicals, as in the case of CF3C(O)H, or by photodissociation to extrude X atoms and form CF3C(O) radicals. The energetics of possible oxidation pathways involving CF3CO, CF3C(O)O and CF3C(O)O2 radicals are investigated using calculations at the UHF/6-31G* and UMP2/6-31G* levels of ab initio theory. In the absence of experimental thermochemical data, calculated heats of reaction are used in discussions of the possible involvement of the intermediates in reactions of atmospheric significance. Issues relating to the chemical stability of CF3C(O)O(x) species are considered.