title: Temperature-Dependent Rate Coefficients for the Reaction of CH2OO with Hydrogen Sulfide.
abstract: The reaction of the simplest Criegee intermediate CH2OO with hydrogen sulfide was measured with transient UV absorption spectroscopy in a temperature-controlled flow reactor, and bimolecular rate coefficients were obtained from 278 to 318 K and from 100 to 500 Torr. The average rate coefficient at 298 K and 100 Torr was (1.7 ± 0.2) × 10-13cm3s-1. The reaction was found to be independent of pressure and exhibited a weak negative temperature dependence. Ab initio quantum chemistry calculations of the temperature-dependent reaction rate coefficient at the QCISD(T)/CBS level are in reasonable agreement with the experiment. The reaction of CH2OO with H2S is 2-3 orders of magnitude faster than the reaction with H2O monomer. Though rates of CH2OO scavenging by water vapor under atmospheric conditions are primarily controlled by the reaction with water dimer, the H2S loss pathway will be dominated by the reaction with monomer. The agreement between experiment and theory for the CH2OO + H2S reaction lends credence to theoretical descriptions of other Criegee intermediate reactions that cannot easily be probed experimentally.
authors.affiliation: Institute of Atomic and Molecular Science, Academia Sinica , Taipei 10617, Taiwan.
authors.forename: Mica C
authors.initials: MC
authors.lastname: Smith
authors.affiliation: Institute of Atomic and Molecular Science, Academia Sinica , Taipei 10617, Taiwan.|Department of Chemistry, National Taiwan University , Taipei 10617, Taiwan.
authors.forename: Wen
authors.initials: W
authors.lastname: Chao
authors.affiliation: Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
authors.forename: Manoj
authors.initials: M
authors.lastname: Kumar
authors.affiliation: Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Francisco
authors.affiliation: Institute of Atomic and Molecular Science, Academia Sinica , Taipei 10617, Taiwan.
authors.forename: Kaito
authors.identifier: http://orcid.org/0000-0003-2339-4295
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Institute of Atomic and Molecular Science, Academia Sinica , Taipei 10617, Taiwan.|Department of Chemistry, National Taiwan University , Taipei 10617, Taiwan.
authors.forename: Jim Jr-Min
authors.initials: JJ
authors.lastname: Lin