Mean-Field Ring Polymer Rates Using a Population Dividing Surface

London, Nathan; Bu, Siyu; Johnson, Britta; Ananth, Nandini

doi:10.1021/acs.jpca.4c00005

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Mean-Field Ring Polymer Rates Using a Population Dividing Surface

London, Nathan·Bu, Siyu·Johnson, Britta·Ananth, Nandini

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Abstract

Mean-field Ring Polymer Molecular Dynamics (MF-RPMD) offers a computationally efficient method for the simulation of reaction rates in multi-level systems. Previous work has established that, to model a nonadiabatic state-to-state reaction accurately, the dividing surface must be chosen to explicitly sample kinked ring polymer configurations where at least one bead is in a different electronic state than the others. Building on this, we introduce a population difference coordinate and a kink-constrained dividing surface, and we test the accuracy of the resulting mean-field rate theory on a series of bilinear coupling model systems. Here, we demonstrate that this new MF-RPMD rate approach is efficient to implement and quantitatively accurate for models over a wide range of driving forces, coupling strengths, and temperatures.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY mean-field rpmd nonadiabatic dynamics reaction rates ring polymer molecular dynamics

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London, Nathan, Bu, Siyu, Johnson, Britta, Ananth, Nandini. 2024-07-08. Mean-Field Ring Polymer Rates Using a Population Dividing Surface. https://doi.org/10.1021/acs.jpca.4c00005

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