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arXiv · 2101.01520

Thermal decay rates of an activated complex in a driven model chemical reaction

Robin Bardakcioglu·Johannes Reiff·Matthias Feldmaier·Jörg Main·Rigoberto Hernandez
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Abstract

Recent work has shown that in a non-thermal, multidimensional system, the trajectories in the activated complex possess different instantaneous and time-averaged reactant decay rates. Under dissipative dynamics, it is known that these trajectories, which are bound on the normally hyperbolic invariant manifold (NHIM), converge to a single trajectory over time. By subjecting these dissipative systems to thermal noise, we find fluctuations in the saddle-bound trajectories and their instantaneous decay rates. Averaging over these instantaneous rates results in the decay rate of the activated complex in a thermal system. We find, that the temperature dependence of the activated complex decay in a thermal system can be linked to the distribution of the phase space resolved decay rates on the NHIM in the non-dissipative case. By adjusting the external driving of the reaction, we show that it is possible to influence how the decay rate of the activated complex changes with rising temperature.

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Robin Bardakcioglu, Johannes Reiff, Matthias Feldmaier, Jörg Main, Rigoberto Hernandez. 2021-01-05. Thermal decay rates of an activated complex in a driven model chemical reaction. https://doi.org/10.1103/physreve.102.062204

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