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Theory Finally Agrees with Experiment for the Dynamics of the Cl + C2H6 Reaction.

ABSTRACT: Since the pioneering reaction dynamics studies of H + H2 in the 1970s, theory increased the system size by one atom in every decade arriving to six-atom reactions in the early 2010s. Here, we take a significant step forward by reporting accurate dynamics simulations for the nine-atom Cl + ethane (C2H6) reaction using a new high-quality spin-orbit-ground-state ab initio potential energy surface. Quasi-classical trajectory simulations on this surface cool the rotational distribution of the HCl product molecules, thereby providing unprecedented agreement with experiment after several previous failed attempts of theory. Unlike Cl + CH4, the Cl + C2H6 reaction is exothermic with an adiabatically submerged transition state, allowing testing of the validity of the Polanyi rules for a negative-barrier reaction.

SUBMITTER: Papp D

PROVIDER: S-EPMC7309313 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Theory Finally Agrees with Experiment for the Dynamics of the Cl + C2H6 Reaction.

Papp Dóra D Tajti Viktor V Győri Tibor T Czakó Gábor G

The journal of physical chemistry letters 20200604 12

Since the pioneering reaction dynamics studies of H + H2 in the 1970s, theory increased the system size by one atom in every decade arriving to six-atom reactions in the early 2010s. Here, we take a significant step forward by reporting accurate dynamics simulations for the nine-atom Cl + ethane (C2H6) reaction using a new high-quality spin-orbit-ground-state ab initio potential energy surface. Quasi-classical trajectory simulations on this surface cool th ...[more]

PMID: 32441943

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