Direct measurements of conformer-dependent reactivity of the Criegee intermediate CH3CHOO

Craig A. Taatjes, Oliver Welz, Arkke J. Eskola, John D. Savee, Adam M. Scheer, Dudley E. Shallcross, Brandon Rotavera, Edmond P F Lee, John M. Dyke, Kam Wah Mok, David L. Osborn, Carl J. Percival

Research output: Journal article publicationJournal articleAcademic researchpeer-review

279 Citations (Scopus)

Abstract

Although carbonyl oxides, "Criegee intermediates," have long been implicated in tropospheric oxidation, there have been few direct measurements of their kinetics, and only for the simplest compound in the class, CH 2OO. Here, we report production and reaction kinetics of the next larger Criegee intermediate, CH3CHOO. Moreover, we independently probed the two distinct CH3CHOO conformers, syn- and anti-, both of which react readily with SO2 and with NO2. We demonstrate that anti-CH3CHOO is substantially more reactive toward water and SO2 than is syn-CH3CHOO. Reaction with water may dominate tropospheric removal of Criegee intermediates and determine their atmospheric concentration. An upper limit is obtained for the reaction of syn-CH 3CHOO with water, and the rate constant for reaction of anti-CH 3CHOO with water is measured as 1.0 × 10-14 ± 0.4 × 10-14 centimeter3 second-1.
Original languageEnglish
Pages (from-to)177-180
Number of pages4
JournalScience
Volume340
Issue number6129
DOIs
Publication statusPublished - 12 Apr 2013

ASJC Scopus subject areas

  • Medicine(all)
  • General

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