Atmospheric Fate of Unsubstituted Alkoxy and Carbonyl Radicals
نویسندگان
چکیده
Alkoxy (R1C(R2)(R3)O•) and Carbonyl (RC(•)O) radicals are important intermediates in the degradation chain of hydrocarbons. Both classes of radicals are subject to competing reaction chan-nels leading to different products which exhibit different ozone formation potentials: Alkoxy radicals (1) Reaction with O2 (kO2, => aldehyde/ketone + HO2); (2) thermal decomposition (kdis, => aldehyde/ketone + alkyl/H); (3) isomerization (kiso, => hydroxyaldehyde/hydroxyketone). Carbonyl Radicals (4) Reaction with O2 (kO2, => RO2, + NO2 => peroxynitrate (alkyl substituted PAN)); (5) thermal decomposition (kdis, => CO + alkyl). In the present work, the ratios kdis/kO2 were determined for a number of unsubstituted C4 and C5 alkoxy and carbonyl radicals, linear and branched, with the main aim of measuring the effect of branching at the α-C atom and of the chain length of R on the ratio kdis/kO2.
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