Fully Coriolis-coupled quantum studies of the H + O2 (upsilon i = 0-2, j i = 0,1) --> OH + O reaction on an accurate potential energy surface: integral cross sections and rate constants.
We present accurate quantum calculations of the integral cross section and rate constant for the H + O2 --> OH + O combustion reaction on a recently developed ab initio potential energy surface using parallelized time-dependent and Chebyshev wavepacket methods. Partial wave contributions up to J = 70 were computed with full Coriolis coupling, which enabled us to obtain the initial state-specified integral cross sections up to 2.0 eV of the collision energy and thermal rate constants up to 3000 K. The integral cross sections show a large reaction threshold due to the quantum endothermicity of the reaction, and they monotonically increase with the collision energy. As a result, the temperature dependence of the rate constant is of the Arrhenius type. In addition, it was found that reactivity is enhanced by reactant vibrational excitation. The calculated thermal rate constant shows a significant improvement over that obtained on the DMBE IV potential, but it still underestimates the experimental consensus.
Lin
Shi Ying
SY
Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA.
Sun
Zhigang
Z
Guo
Hua
H
Zhang
Dong Hui
DH
Honvault
Pascal
P
Xie
Daiqian
D
Lee
Soo-Y
SY
D006859:Hydrogen / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D008956:Models, Chemical; D010100:Oxygen / Q000737:chemistry*; D011789:Quantum Theory; D012399:Rotation; D013499:Surface Properties; D013816:Thermodynamics; D013997:Time Factors; D014732:Vibration
D017665:Hydroxyl Radical; D006859:Hydrogen; D010100:Oxygen