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Updated: Feb 26, 2026

Reaction Kinetics and Combustion Dynamics of I4O9 and Aluminum Mixtures
Published on: November 7, 2016
A kinetic study of the CH2OO Criegee intermediate reaction with SO2, (H2O)2, CH2I2 and I atoms using OH laser induced
Yiqiang Liu1, Fenghua Liu, Siyue Liu
1State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China. wrdong@dicp.ac.cn xmyang@dicp.ac.cn.
Abstract:
The OH laser induced fluorescence method was used to study the kinetics of CH2OO reacting with SO2, (H2O)2, CH2I2 and I atoms. Decay of CH2OO is not strictly first-order since its self-reaction is rapid. With this consideration, we derived the rate coefficient of CH2OO + SO2/(H2O)2/CH2I2/I taking into account the contribution of the CH2OO self-reaction. For the CH2OO + SO2 reaction, the rate coefficient is measured to be (3.88 ± 0.13) × 10-11 cm3 molecule-1 s-1 at 10 Torr, which agrees very well with a previously reported value obtained by directly monitoring CH2OO using the UV absorption method with the CH2OO self-reaction considered. We did not observe obvious evidence for SO2 catalysed CH2OO isomerization or the intersystem crossing effect in this reaction. CH2OO + (H2O)2 is supposed to account for the major sink of CH2OO in the atmosphere, but previous rate coefficient measurements were not in good agreement. We have revisited this reaction including the self-reaction of CH2OO and obtained the rate coefficient to be (7.53 ± 0.38) × 10-12 cm3 molecule-1 s-1 at 60 Torr and 300 K. The rate coefficients of CH2OO + CH2I2 and CH2OO + I were measured to be (5.2 ± 2.6) × 10-14 and (2.2 ± 1.1) × 10-12 cm3 molecule-1 s-1 respectively.
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