Premium
Temperature‐dependent kinetics of the simplest Criegee intermediate reaction with dimethyl sulfoxide
Author(s) -
Li YuLin,
Lin ChunYu,
Lin YenHsiu,
Lin Jim JrMin
Publication year - 2020
Publication title -
journal of the chinese chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.329
H-Index - 45
eISSN - 2192-6549
pISSN - 0009-4536
DOI - 10.1002/jccs.202000206
Subject(s) - chemistry , arrhenius equation , dimethyl sulfide , dimethyl sulfoxide , torr , reaction rate constant , kinetics , activation energy , photochemistry , reactivity (psychology) , arrhenius plot , sulfur , analytical chemistry (journal) , organic chemistry , thermodynamics , physics , quantum mechanics , medicine , alternative medicine , pathology
Criegee intermediates are thought to play roles in atmospheric chemistry, including OH radical formation, oxidation of SO 2 , NO 2 , etc. CH 2 OO is the simplest Criegee intermediate, of which the reactivity has been a hot topic. Here we investigated the kinetics of CH 2 OO reaction with dimethyl sulfoxide (DMSO) under 278–349 K and 10–150 Torr. DMSO is an important species formed in the oxidation of dimethyl sulfide in the biogenic sulfur cycle. The concentration of CH 2 OO was monitored in real‐time via its mid‐infrared absorption band at about 1,286 cm −1 (Q branch of the ν 4 band) with a high‐resolution quantum cascade laser spectrometer. The 298 K bimolecular rate coefficient was determined to be k 298 = (2.3 ± 0.3) × 10 −12 cm 3 /s at 30 Torr with an Arrhenius activation energy of −3.9 ± 0.2 kcal/mol and a weak pressure dependence for pressures higher than 30 Torr ( k 298 = (2.8 ± 0.3) × 10 −12 cm 3 /s at 100 Torr). The reaction is speculated to undergo a five‐membered ring intermediate, analogous to that of CH 2 OO with SO 2 . The negative activation energy indicates that the rate‐determining transition state is submerged. The magnitude of the reaction rate coefficient lies in between those of CH 2 OO reactions with (CH 3 ) 2 CO and with SO 2 .