Projects per year
Abstract
The rate coefficients for gas-phase reaction of trifluoroacetic acid (TFA) with two Criegee intermediates, formaldehyde oxide and acetone oxide, decrease with increasing temperature in the range 240 – 340 K. The rate coefficients k(CH2OO + CF3COOH) = (3.4 +/- 0.3) x 10-10 cm3 s-1 and k((CH3)2COO + CF3COOH) = (6.1 +/- 0.2) x 10-10 cm3 s-1 at 294 K exceed estimates for collision-limited values, suggesting rate enhancement by capture mechanisms because of the large permanent dipole moments of the two reactants. The observed temperature dependence is attributed to competitive stabilization of a pre-reactive complex. Fits to a model incorporating this complex formation give k [cm3 s-1] = (3.8 +/- 2.6) x 10-18 T2 exp((1620 +/- 180)/T) + 2.5 x 10-10 and k [cm3 s-1] = (4.9 +/- 4.1) x 10-18 T2 exp((1620 +/- 230)/T) + 5.2 x 10-10 for the CH2OO + CF3COOH and (CH3)2COO + CF3COOH reactions, respectively. The consequences are explored for removal of TFA from the atmosphere by reaction with biogenic Criegee intermediates.
Original language | English |
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Pages (from-to) | 9172-9175 |
Number of pages | 4 |
Journal | Angewandte Chemie - International Edition |
Volume | 129 |
Issue number | 31 |
Early online date | 29 Jun 2017 |
DOIs | |
Publication status | Published - 24 Jul 2017 |
Keywords
- KINETICS
- Reactive Intermediates
- Atmospheric Chemistry;
- Criegee Biradical
- Zwitterion
- TFA
Fingerprint
Dive into the research topics of 'Temperature dependence of the rates of reaction of trifluoroacetic acid with Criegee intermediates'. Together they form a unique fingerprint.Projects
- 4 Finished
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Kinetic Studies of Reactive Intermediates from the Oxidation of Atmospheric Alkenes
Orr-Ewing, A. J. (Principal Investigator)
1/04/17 → 30/09/20
Project: Research
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HOMER: Fellowship - Max McGillen
Shallcross, D. E. (Principal Investigator)
4/04/16 → 3/04/18
Project: Research
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Gas phase studies of the kinetics of Criegee Intermediates
Shallcross, D. E. (Principal Investigator) & Orr-Ewing, A. J. (Co-Principal Investigator)
30/06/13 → 31/12/16
Project: Research
Profiles
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Professor Dudley E Shallcross
- School of Chemistry - Professor of Atmospheric Chemistry
- Cabot Institute for the Environment
- Atmospheric Chemistry
Person: Academic , Member