title: Direct ab initio dynamics study of radical C4H (X̃2Σ+) + CH4 reaction.
abstract: The methane (CH(4)) hydrogen abstraction reaction by linear butadiynyl radical C(4)H (CCCCH) has been investigated by direct ab initio dynamics over a wide temperature range of 100-3000 K, theoretically. The potential energy surfaces (PESs) have been constructed at the CCSD(T)/aug-cc-pVTZ//BB1K/6-311G(d,p) levels of theory. Two different hydrogen abstraction channels by C(1) and C(4) of C(4)H (C(1)C(2)C(3)C(4)H) have been considered. The results indicate that the C(1) position of C(4)H is a more reactive site. The electron transfer behaviors of two possible channels are also analyzed by quasi-restricted orbital (QRO) in detail. The rate constants calculated by canonical variational transition-state theory (CVT) with the small-curvature tunneling correction (SCT) are in excellent agreement with available experimental values. The normal and three-parameter expressions of Arrhenius rate constants are also provided within 100-3000 K. It is expected to be helpful for further studies on the reaction dynamics behaviors over a wide temperature range where no experimental data is available so far.
authors: State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, People's Republic of China.
authors: Rui-Ping
authors: RP
authors: Huo
authors: Xiang
authors: X
authors: Zhang
authors: Xu-Ri
authors: XR
authors: Huang
authors: Ji-Lai
authors: JL
authors: Li
authors: Chia-Chung
authors: CC
authors: Sun
mesh_terms: D005609:Free Radicals / Q000737:chemistry; D008697:Methane / Q000737:chemistry*; D011789:Quantum Theory; D013696:Temperature
chemical_list: D005609:Free Radicals; D008697:Methane