The potential energy surface (PES) for the reaction of an oxygen atom with
a fluorinated methyl radical has been studied using the G2MP2 level of theo
ry. The calculations reveal an association-elimination mechanism. The addit
ion reaction of O(P-3) to CH2F produces an energy-rich intermediate OCH2F*
which subsequently decomposes irreversibly. Five production channels of OCH
2F* are found: H + CHFO, HF + HCO, CHFOH, F + CH2O and H-2 + FCO. CHFOH can
decompose through six production channels: H + CHFO, HF + HCO, H + HCOF, H
-2 + FCO, F + HCOH and OH + CHF. Based on the present ab initio PES, the ki
netic characteristics of the O(P-3) + CH2F reaction are estimated. The ener
gy-specific rate constants for the unimolecular decomposition of OCH,F are
calculated by RRKM theory. H + CHFO are predicted to be the major products.
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