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DOE OSTI · 1999112

Exact-Factorization-Based Surface Hopping for Multistate Dynamics

Vindel-Zandbergen, Patricia·Matsika, Spiridoula·Maitra, Neepa T.
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Abstract

A surface-hopping algorithm recently derived from the exact factorization approach, SHXF, introduces an additional term in the electronic equation of surface hopping that couples electronic states through the quantum momentum. Furthermore, this term not only provides a first-principles description of decoherence, but here we show it is crucial to accurately capture nonadiabatic dynamics when more than two states are occupied at any given time. Using a vibronic coupling model of the uracil cation, we show that the lack of this term in traditional surface-hopping methods, including those with decoherence corrections, leads to failure to predict the dynamics through a three-state intersection, while SHXF performs similarly to the multiconfiguration time-dependent Hartree quantum dynamics benchmark.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSAlgorithmsCationsChemical calculationsComputational chemistryUracil

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Vindel-Zandbergen, Patricia, Matsika, Spiridoula, Maitra, Neepa T.. 2022-02-16. Exact-Factorization-Based Surface Hopping for Multistate Dynamics. https://doi.org/10.1021/acs.jpclett.1c04132

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