Post Transition State Dynamics in Gas Phase Reactivity : The Importance of Bifurcations and Rotational Activation. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of Chemical Theory and Computation Année : 2016

Post Transition State Dynamics in Gas Phase Reactivity : The Importance of Bifurcations and Rotational Activation.

Résumé

Beyond the established use of thermodynamic vs kinetic control to explain chemical reaction selectivity, the concept of bifurcations on a potential energy surface (PES) is proving to be of pivotal importance with regard to selectivity. In this article, we studied by means of post-transition state (TS) direct dynamics simulations the effect that vibrational and rotational excitation at the TS may have on selectivity on a bifurcating PES. With this aim, we studied the post-TS unimolecular reactivity of the [Ca(formamide)]2+ ion, for which Coulomb explosion and neutral loss reactions compete. The PES exhibits different kinds of nonintrinsic reaction coordinate (IRC) dynamics, among them PES bifurcations, which direct the trajectories to multiple reaction paths after passing the TS. Direct dynamics simulations were used to distinguish between the bifurcation non-IRC dynamics and non-IRC dynamics arising from atomistic motions directing the trajectories away from the IRC. Overall, we corroborated the idea that kinetic selectivity often does not reduce to a simple choice between paths with different barrier heights and instead dynamical behavior after passing the TS may be crucial. Importantly, rotational excitation may play a pivotal role on the reaction selectivity favoring nonthermodynamic products.
Fichier non déposé

Dates et versions

hal-01386209 , version 1 (23-10-2016)

Identifiants

Citer

Ana Martín-Sómer, Manuel Yáñez, William L. Hase, Marie-Pierre Gaigeot, Riccardo Spezia. Post Transition State Dynamics in Gas Phase Reactivity : The Importance of Bifurcations and Rotational Activation.. Journal of Chemical Theory and Computation, 2016, 12 (3), pp.974-982. ⟨10.1021/acs.jctc.5b01135⟩. ⟨hal-01386209⟩
80 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More