Nonstatistical dynamics on potentials exhibiting reaction path bifurcations and valley-ridge inflection points
Peter Collins1, Barry K Carpenter, Gregory S Ezra
1School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom.
The Journal of Chemical Physics
|October 29, 2013
Summary
Minor potential changes significantly alter reaction dynamics. Dissipation complicates product ratios non-monotonically, with VRI region dynamics playing a minor role except in highly dissipative cases.
Area of Science:
- Chemical Dynamics
- Reaction Mechanisms
- Computational Chemistry
Background:
- Investigating reaction dynamics near potential energy surface features like valley ridge inflection (VRI) points is crucial for understanding chemical reactions.
- Post-transition state bifurcation influences product distribution, making it a key area of study.
Purpose of the Study:
- To explore reaction dynamics on a model potential energy surface with post-transition state bifurcation near a VRI point.
- To analyze the impact of minor potential variations and dissipative effects on product yields.
Main Methods:
- Computation of fractional product yields.
- Simulation of dynamics with and without dissipation.
- Analysis of reaction pathways around the VRI point.
Main Results:
- Small changes in the potential energy surface lead to substantial alterations in reaction dynamics.
- Dissipative effects introduce complex, non-monotonic dependence of product ratios on the dissipation parameter.
- VRI region dynamics have minimal influence on product ratios, except under highly dissipative conditions.
Conclusions:
- Reaction dynamics are highly sensitive to subtle features of the potential energy surface.
- Dissipation significantly alters product selectivity in a non-trivial manner.
- The VRI point's role in determining product ratios is limited, primarily relevant in strongly dissipative systems.
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