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Measurements of Rate Constants for OH Reactions with Bromoform (CHBr3), CHBr2Cl, CHBrCl2, and Epichlorohydrin C3H5ClO)
Published
Author(s)
Vladimir L. Orkin, Victor Khamaganov, S N. Kozlov, Michael J. Kurylo III
Abstract
Measurements of the rate constants for the gas phase reactions of OH radicals with bromoform (CHBr3) and epichlorohydrin (C3H5ClO) were performed using a flash photolysis resonance-fluorescence technique over the temperature range 230 K to 370 K. The temperature dependences of the rate constants can be represented by the following expressions: kBF(230-370 K) = (9.94 ±0.76)×10-13×exp{-(387±22)/T} cm3 molecule-1 s-1 kECH(230-370 K) = 1.052×10-14×(T/298)5.156×exp{+1082/T} cm3 molecule-1 s-1. Rate constants for the reactions of OH with CHCl2Br and CHClBr2 were measured between 230 K and 330 K. They can be represented by the following expressions: kDCBM(230-330 K) = (8.9 ±1.3)×10-13×exp{-(500±41)/T} cm3 molecule-1 s-1; kCDBM(230-330 K) = (9.4 ±2.2)×10-13×exp{-(440±67)/T} cm3 molecule-1 s-1. The atmospheric lifetimes due to reactions with tropospheric OH were estimated to be 57 days, 39 days, 73 days, and 97 days, respectively. The total local atmospheric lifetimes of the Br-containing methanes were also calculated.
Orkin, V.
, Khamaganov, V.
, Kozlov, S.
and Kurylo, M.
(2013),
Measurements of Rate Constants for OH Reactions with Bromoform (CHBr3), CHBr2Cl, CHBrCl2, and Epichlorohydrin C3H5ClO), Journal of Physical Chemistry A, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=912529
(Accessed October 14, 2025)