Theoretical Studies of the Reactions CFxH3−xCOOR+Cl and CF3COOCH3+OH |
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Authors: | Feng‐Yang Bai Xiao‐Le Zhu Zi‐Man Jia Xu Wang Yan‐Qiu Sun Prof Rong‐Shun Wang Prof Xiu‐Mei Pan |
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Affiliation: | Faculty of Chemistry, Institute of Functional Material Chemistry, Northeast Normal University, 130024 Changchun (People's Republic of China) |
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Abstract: | The mechanism and kinetics of the reactions of CF3COOCH2CH3, CF2HCOOCH3, and CF3COOCH3 with Cl and OH radicals are studied using the B3LYP, MP2, BHandHLYP, and M06‐2X methods with the 6‐311G(d,p) basis set. The study is further refined by using the CCSD(T) and QCISD(T)/6‐311++G(d,p) methods. Seven hydrogen‐abstraction channels are found. All the rate constants, computed by a dual‐level direct method with a small‐curvature tunneling correction, are in good agreement with the experimental data. The tunneling effect is found to be important for the calculated rate constants in the low‐temperature range. For the reaction of CF3COOCH2CH3+Cl, H‐abstraction from the CH2 group is found to be the dominant reaction channel. The standard enthalpies of formation for the species are also calculated. The Arrhenius expressions are fitted within 200–1000 K as kT(1)=8.4×10?20T 2.63exp(381.28/T), kT(2)=2.95×10?21T 3.13exp(?103.21/T), kT(3)=1.25×10?23T 3.37exp(791.98/T), and kT(4)=4.53×10?22T 3.07exp(465.00/T). |
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Keywords: | computational chemistry H‐abstraction hydrofluorinated esters rate constants transition state |
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