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Differences in the Abilities to Mechanically Eliminate Activation Energies for Unimolecular and Bimolecular Reactions.

ABSTRACT: Mechanochemistry, i.e. the application of forces, F, at the molecular level, has attracted significant interest as a means of controlling chemical reactions. The present study uses quantum chemical calculations to explore the abilities to mechanically eliminate activation energies, ?E(‡), for unimolecular and bimolecular reactions. The results demonstrate that ?E(‡) can be eliminated for unimolecular reactions by applying sufficiently large F along directions that move the reactant and/or transition state (TS) structures parallel to the zero-F reaction coordinate, S0. In contrast, eliminating ?E(‡) for bimolecular reactions requires the reactant to undergo a force-induced shift parallel to S0 irrespective of changes in the TS. Meeting this requirement depends upon the coupling between F and S0 in the reactant. The insights regarding the differences in eliminating ?E(‡) for unimolecular and bimolecular reactions, and the requirements for eliminating ?E(‡), may be useful in practical efforts to control reactions mechanochemically.

SUBMITTER: Kochhar GS

PROVIDER: S-EPMC4789786 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Differences in the Abilities to Mechanically Eliminate Activation Energies for Unimolecular and Bimolecular Reactions.

Kochhar Gurpaul S GS Mosey Nicholas J NJ

Scientific reports 20160314

Mechanochemistry, i.e. the application of forces, F, at the molecular level, has attracted significant interest as a means of controlling chemical reactions. The present study uses quantum chemical calculations to explore the abilities to mechanically eliminate activation energies, ΔE(‡), for unimolecular and bimolecular reactions. The results demonstrate that ΔE(‡) can be eliminated for unimolecular reactions by applying sufficiently large F along directions that move the reactant and/or transi ...[more]

PMID: 26972114

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Differences in the Abilities to Mechanically Eliminate Activation Energies for Unimolecular and Bimolecular Reactions.

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Differences in the Abilities to Mechanically Eliminate Activation Energies for Unimolecular and Bimolecular Reactions.

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