An experimental and theoretical study on the kinetic isotope effect of C2H6 and C2D6 reaction with OH

An ONIOM-Based High-Level Thermochemistry Study on Hydrogen Abstraction Reactions of Large Straight-Chain Alkanes by Hydrogen, Hydroxyl, and Hydroperoxyl Radicals

“…For the reaction systems of n-C n H 2n+2 + OH, Gruber and Czako [74] calculated the reactions of CH 4 and C 2 H 6 with OH at the CCSD(T)-F12b/aug-cc-pVnZ//CCSD(T)-F12b/augcc-pVTZ level. Khaled et al [48] studied the reaction of C 2 H 6 with OH at the CCSD(T)/cc-pV(T,Q)Z//MP2/cc-pVTZ level. Despite employing these very high-level methods, the differences in results were generally less than 0.4 kcal/mol when compared with the ONIOM method.…”

“…a Gruber and Czakó [74] at the CCSD(T)-F12b/aug-cc-pVnZ//CCSD(T)-F12b/aug-cc-pVTZ. b Khaled et al [48] at the CCSD(T)/cc-pV(T,Q)Z//MP2/cc-pVTZ. c Sivaramakrishnan et al [50] at the G3//B3LYP level.…”

“…Regarding the use of high-level ab initio chemical kinetics for hydrocarbon molecules, most previous studies have primarily focused on relatively small hydrocarbon molecules [37,42,[47][48][49][50][51][52]. This focus is mainly because the prevalent high-level methods based on electronic structure theory are computationally demanding for large hydrocarbon molecules.…”

Direct and steady state rate constants of C2H6 + X (X = H, Cl, OH): influence of the van der Waals well

“…The OH + C 2 H 6 reaction is of particular importance because the hydroxyl radical is a principal chain carrier in hydrocarbon combustion. Experimentally, Tully et al 42 measured the rate constants of OH + C 2 H 6 using the laser photolysis/laserinduced fluorescence technique over the temperature range of 293-705 K. Krasnoperov et al 43 reported the rate constants using the reflected shock tube technique in the temperature range of 822-1367 K. Khaled et al 44 also determined the rate constants using the low-pressure shock tube facility over the temperature range of 800-1350 K. For this reaction, electronic structure calculations 22,[45][46][47][48] indicated that the classical potential energy barrier is in the range of 2.8 to 4.0 kcal mol À1 . Rangel et al 22 reported a deep potential energy well for the reactant complex, and constructed an analytical fulldimensional potential energy surface for OH + C 2 H 6 (PES-2020), in which the potential energy wells of the reactant complex and potential energy barrier are À2.70 and 3.76 kcal mol À1 , respectively.…”

Benchmark ab initio characterization of the abstraction and substitution pathways of the OH + CH4/C2H6 reactions

“…17,18,28,30,31 The stationary points along the HA pathway were characterized by various ab initio and density functional methods reporting pre-and postreaction complexes separated by a transition state for each reaction. 19,22,23,27,28,33,35,38 In the case of the OH + CH 4 system, the CH 4 Á Á ÁOH and H 2 OÁ Á ÁCH 3 complexes were also studied by different experimental techniques using stimulated Raman, infrared and electronic excitation, 24,36,37 photoelectron-photofragment coincidence, 34 and infrared spectroscopy in helium nanodroplets. 26,32 Furthermore, detailed reactive scattering experiments were performed for the different isotope-variants of the OH + CH 4 -H 2 O + CH 3 reaction by Liu and co-workers.…”