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Rich Dynamics Underlying Solution Reactions Revealed by Sampling and Data Mining of Reactive Trajectories.

ABSTRACT: Efficient sampling in both configuration and trajectory spaces, combined with mechanism analyses via data mining, allows a systematic investigation of the thermodynamics, kinetics, and molecular-detailed dynamics of chemical reactions in solution. Through a Bayesian learning algorithm, the reaction coordinate(s) of a (retro-)Claisen rearrangement in bulk water was variationally optimized. The bond formation/breakage was found to couple with intramolecular charge separation and dipole change, and significant dynamic solvent effects manifest, leading to the "in-water" acceleration of Claisen rearrangement. In addition, the vibrational modes of the reactant and the solvation states are significantly coupled to the reaction dynamics, leading to heterogeneous and oscillatory reaction paths. The calculated reaction rate is well interpreted by the Kramers' theory with a diffusion term accounting for solvent-solute interactions. These findings demonstrated that the reaction mechanisms can be complicated in homogeneous solutions since the solvent-solute interactions can profoundly influence the reaction dynamics and the energy transfer process.

SUBMITTER: Zhang J

PROVIDER: S-EPMC5445542 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Rich Dynamics Underlying Solution Reactions Revealed by Sampling and Data Mining of Reactive Trajectories.

Zhang Jun J Zhang Zhen Z Yang Yi Isaac YI Liu Sirui S Yang Lijiang L Gao Yi Qin YQ

ACS central science 20170415 5

Efficient sampling in both configuration and trajectory spaces, combined with mechanism analyses via data mining, allows a systematic investigation of the thermodynamics, kinetics, and molecular-detailed dynamics of chemical reactions in solution. Through a Bayesian learning algorithm, the reaction coordinate(s) of a (retro-)Claisen rearrangement in bulk water was variationally optimized. The bond formation/breakage was found to couple with intramolecular charge separation and dipole change, and ...[more]

PMID: 28573202

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Rich Dynamics Underlying Solution Reactions Revealed by Sampling and Data Mining of Reactive Trajectories.

Publications

Rich Dynamics Underlying Solution Reactions Revealed by Sampling and Data Mining of Reactive Trajectories.

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