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arXiv · 2303.01376

Energy-Conserving Coupled Trajectory Mixed Quantum Classical Dynamics

Evaristo Villaseco Arribas·Neepa T. Maitra
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Abstract

The coupled-trajectory mixed quantum classical method (CTMQC), derived from the exact factorization approach, has successfully predicted photo-chemical dynamics in a number of interesting molecules, capturing population transfer and decoherence from first-principles. However, due to the approximations made, CTMQC does not guarantee energy conservation. We propose a modified algorithm, CTMQC-E, which redefines the integrated force in the coupled-trajectory term so to restore energy conservation, and demonstrate its accuracy on scattering in Tully's extended coupling region model and photoisomerization in a retinal chromophore model.

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Evaristo Villaseco Arribas, Neepa T. Maitra. 2023-03-02. Energy-Conserving Coupled Trajectory Mixed Quantum Classical Dynamics. https://doi.org/10.1063/5.0149116

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