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Different flavors of exact-factorization-based mixed quantum-classical methods for multistate dynamics

Arribas, Evaristo Villaseco·Vindel-Zandbergen, Patricia·Roy, Saswata·Maitra, Neepa T.
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Abstract

Here, the exact factorization approach has led to the development of new mixed quantum-classical methods for simulating coupled electron–ion dynamics. We compare their performance for dynamics when more than two electronic states are occupied at a given time, and analyze: (1) the use of coupled versus auxiliary trajectories in evaluating the electron–nuclear correlation terms, (2) the approximation of using these terms within surface-hopping and Ehrenfest frameworks, and (3) the relevance of the exact conditions of zero population transfer away from nonadiabatic coupling regions and total energy conservation. Dynamics through the three-state conical intersection in the uracil radical cation as well as polaritonic models in one dimension are studied.

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Arribas, Evaristo Villaseco, Vindel-Zandbergen, Patricia, Roy, Saswata, Maitra, Neepa T.. 2023-09-19. Different flavors of exact-factorization-based mixed quantum-classical methods for multistate dynamics. https://doi.org/10.1039/d3cp03464j

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