title: A permutationally invariant full-dimensional ab initio potential energy surface for the abstraction and exchange channels of the H + CH4 system.
abstract: We report a permutationally invariant global potential energy surface (PES) for the H + CH4 system based on ∼63,000 data points calculated at a high ab initio level (UCCSD(T)-F12a/AVTZ) using the recently proposed permutation invariant polynomial-neural network method. The small fitting error (5.1 meV) indicates a faithful representation of the ab initio points over a large configuration space. The rate coefficients calculated on the PES using tunneling corrected transition-state theory and quasi-classical trajectory are found to agree well with the available experimental and previous quantum dynamical results. The calculated total reaction probabilities (Jtot = 0) including the abstraction and exchange channels using the new potential by a reduced dimensional quantum dynamic method are essentially the same as those on the Xu-Chen-Zhang PES [Chin. J. Chem. Phys. 27, 373 (2014)].
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Daiqian
authors.initials: D
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Dong H
authors.initials: DH
authors.lastname: Zhang
authors.affiliation: Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Guo
mesh_terms: D006859:Hydrogen / Q000737:chemistry*; D007700:Kinetics; D008697:Methane / Q000737:chemistry*; D008956:Models, Chemical; D011336:Probability; D011789:Quantum Theory
chemical_list: D006859:Hydrogen; D008697:Methane