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Reactivity oscillation in the heavy-light-heavy Cl + CH4 reaction.

ABSTRACT: It has long been predicted that oscillatory behavior exists in reactivity as a function of collision energy for heavy-light-heavy (HLH) chemical reactions in which a light atom is transferred between two heavy atoms or groups of atoms, but direct observation of such a behavior in bimolecular reactions remains a challenge. Here we report a joint theoretical and crossed-molecular-beam study on the Cl + CH4 ? HCl + CH3 reaction. A distinctive peak at a collision energy of 0.15 eV for the CH3(v = 0) product was experimentally detected in the backward scattering direction. Detailed quantum-dynamics calculations on a highly accurate potential energy surface revealed that this feature originates from the reactivity oscillation in this HLH polyatomic reaction. We anticipate that such reactivity oscillations exist in many HLH reactions involving polyatomic reagents.

SUBMITTER: Chen Z

PROVIDER: S-EPMC7196785 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Reactivity oscillation in the heavy-light-heavy Cl + CH4 reaction.

Chen Zhen Z Chen Jun J Chen Rongjun R Xie Ting T Wang Xingan X Liu Shu S Wu Guorong G Dai Dongxu D Yang Xueming X Zhang Dong H DH

Proceedings of the National Academy of Sciences of the United States of America 20200410 17

It has long been predicted that oscillatory behavior exists in reactivity as a function of collision energy for heavy-light-heavy (HLH) chemical reactions in which a light atom is transferred between two heavy atoms or groups of atoms, but direct observation of such a behavior in bimolecular reactions remains a challenge. Here we report a joint theoretical and crossed-molecular-beam study on the Cl + CH4 → HCl + CH3 reaction. A distinctive peak at a collision energy of 0.15 ...[more]

PMID: 32277024

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