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Ab Initio Molecular Dynamics Simulation Study on the Stereo Reactions between Atomic Oxygen Anion and Methane.

ABSTRACT: Ion⁻molecule reaction between atomic oxygen anion (O-) and methane (CH₄) has been systematically investigated employing the on-the-fly ab initio molecular dynamics simulations. Besides the major H-abstraction process as the exothermic reaction studied widely, an endothermic pathway to produce OCH₃- and H is also observed in this study. Three typical O- attack modes with reference to the pyramid structure of CH₄ fixed in space have been considered. It was found that the internal motions of the radical products are significantly dependent on the O- attack modes. As for the reaction between O- and the thermally vibrating CH₄, the major pathway to produce OH- and CH₃ is preferred by the direct H-abstraction and the minor pathway to produce H and OCH₃- is the roaming reaction via the transient negative ion [HO-CH₃]-.

SUBMITTER: Wang W

PROVIDER: S-EPMC6222880 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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