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arXiv · 2207.05556

Realization of the Trajectory Propagation in the MM-SQC Dynamics by Using Machine Learning

Kunni Lin·Jiawei Peng·Chao Xu·Feng Long Gu·Zhenggang Lan
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Abstract

The supervised machine learning (ML) approach is applied to realize the trajectory-based nonadiabatic dynamics within the framework of the symmetrical quasi-classical dynamics method based on the Meyer-Miller mapping Hamiltonian (MM-SQC). After the construction of the long short-term memory recurrent neural network (LSTM-RNN) model, it is used to perform the entire trajectory evolutions from initial sampling conditions. The proposed idea is proven to be reliable and accurate in the simulations of the dynamics of several site-exciton electron-phonon coupling models, which cover two-site and three-site systems with biased and unbiased energy levels, as well as include a few or many phonon modes. The LSTM-RNN approach also shows the powerful ability to obtain the accurate and stable results for the long-time evolutions. It indicates that the LSTM-RNN model perfectly captures of dynamical correction information in the trajectory evolution in the MM-SQC dynamics. Our work provides the possibility to employ the ML methods in the simulation of the trajectory-based nonadiabatic dynamic of complex systems with a large number of degrees of freedoms.

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Kunni Lin, Jiawei Peng, Chao Xu, Feng Long Gu, Zhenggang Lan. 2022-07-11. Realization of the Trajectory Propagation in the MM-SQC Dynamics by Using Machine Learning. https://arxiv.org/abs/2207.05556

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