An FTIR spectroscopic study of the reactions Br + CH3CHO → HBr + CH3CO and CH3C(O)OO + NO2 ⇌ CH3C(O)OONO2 (PAN)

Abstract

AbstractBased on an FTIR‐product study of the photolysis of mixtures containing Br2CH3CHO and Br2CH3CHOHCHO in 700 torr of N2, the rate constant for the reaction Br + CH3CHO → HBr + CH3CO was determined to be 3.7 × 10−12 cm3 molecule−1 s−1. In addition, the selective photochemical generation of Br at λ > 400 nm in mixtures containing Br2CH3CHO14NO2 (or 15NO2)O2 was shown to serve as a quantitative preparation method for the corresponding nitrogen‐isotope labeled CH3C(O)OONO2 (PAN). From the dark‐decay rates of 15N‐labeled PAN in large excess 14NO2, the rate constant for the unimolecular reaction CH3C(O)OO15NO2 → CH3C(O)OO + 15NO2 was measured to be 3.3 (±0.2) × 10−4 s−1 at 297 ± 0.5 K.