TY - JOUR
T1 - A product yield study of the reaction of HO 2 radicals with ethyl peroxy (C 2H 5O 2), acetyl peroxy (CH 3C(O)O 2), and acetonyl peroxy (CH 3C(O)CH 2O 2) radicals
AU - Hasson, Alam S.
AU - Tyndall, Geoffrey S.
AU - Orlando, John J.
PY - 2004/7/15
Y1 - 2004/7/15
N2 - The reaction between HO 2 and RO 2 radicals represents an important chemical sink for HO x radicals in the atmosphere. On the basis of a few product yield studies, these reactions are believed to form hydroperoxides almost exclusively (R8a), although several different reaction channels may be thermodynamically accessible (R8a-d): RO 2 + HO 2 → ROOh + O 2 (R8a); RO 2 + HO 2 → ROH + O 3 (R8b); RO 2 + HO 2 → RO + OH + O 2 (R8c); and RO 2 + HO 2 → R′CHO + H 2O + O 2 (R8d). Branching ratios for reaction R8 were measured for three organic peroxy radicals: ethyl peroxy (C 2H 5O 2), acetyl peroxy (CH 3C(O)O 2), and acetonyl peroxy (CH 3C(O)CH 2O 2) radicals. Product yields were measured using a combination of long-path Fourier transform infrared spectroscopy and high-performance liquid chromatography with fluorescence detection. Measured branching ratios for the reaction of the three organic peroxy radicals with HO 2 are as follows: ethyl peroxy, Y 8a-ETH > 0.93 ± 0.10, Y 8b-ETH = Y 8c-ETH = Y 8d-ETH = 0; acetyl peroxy, Y 8a-ACT = 0.40 ± 0.16, Y 8b-ACT = 0.20 ± 0.08, Y 8c-ACT = 0.40 ± 0.16, and Y 8d-ACT = 0; acetonyl peroxy, Y 8a-ACN = 0.33 ± 0.10, Y 8b-ACN = Y 8d-ACN = 0, and Y 8c-ACN = 0.67 ± 0.20. The atmospheric implications of these branching ratios are discussed.
AB - The reaction between HO 2 and RO 2 radicals represents an important chemical sink for HO x radicals in the atmosphere. On the basis of a few product yield studies, these reactions are believed to form hydroperoxides almost exclusively (R8a), although several different reaction channels may be thermodynamically accessible (R8a-d): RO 2 + HO 2 → ROOh + O 2 (R8a); RO 2 + HO 2 → ROH + O 3 (R8b); RO 2 + HO 2 → RO + OH + O 2 (R8c); and RO 2 + HO 2 → R′CHO + H 2O + O 2 (R8d). Branching ratios for reaction R8 were measured for three organic peroxy radicals: ethyl peroxy (C 2H 5O 2), acetyl peroxy (CH 3C(O)O 2), and acetonyl peroxy (CH 3C(O)CH 2O 2) radicals. Product yields were measured using a combination of long-path Fourier transform infrared spectroscopy and high-performance liquid chromatography with fluorescence detection. Measured branching ratios for the reaction of the three organic peroxy radicals with HO 2 are as follows: ethyl peroxy, Y 8a-ETH > 0.93 ± 0.10, Y 8b-ETH = Y 8c-ETH = Y 8d-ETH = 0; acetyl peroxy, Y 8a-ACT = 0.40 ± 0.16, Y 8b-ACT = 0.20 ± 0.08, Y 8c-ACT = 0.40 ± 0.16, and Y 8d-ACT = 0; acetonyl peroxy, Y 8a-ACN = 0.33 ± 0.10, Y 8b-ACN = Y 8d-ACN = 0, and Y 8c-ACN = 0.67 ± 0.20. The atmospheric implications of these branching ratios are discussed.
UR - https://www.scopus.com/pages/publications/3242875153
U2 - 10.1021/jp048873t
DO - 10.1021/jp048873t
M3 - Article
AN - SCOPUS:3242875153
SN - 1089-5639
VL - 108
SP - 5979
EP - 5989
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 28
ER -