SPADE 1.0: A Simulation Package for Non-Adiabatic Dynamics in Extended Systems

Journal of Chemical Theory and Computation, Год журнала: 2025, Номер unknown

Опубликована: Март 24, 2025

Nonadiabatic molecular dynamics (NAMD) simulations are crucial for revealing the underlying mechanisms of photochemical and photophysical processes. Typical NAMD simulation software packages rely on on-the-fly ab initio electronic structure nonadiabatic coupling calculations, thus become challenging when dealing with large complex systems. We here introduce a new Simulation Package non-Adiabatic Dynamics in Extended systems (SPADE), which is designed to address limitations traditional surface hopping methods these problems. By design, SPADE enables users define arbitrary quasi-diabatic Hamiltonians through parametrized functions incorporates variety algorithms (e.g., global flux probabilities, crossing decoherence corrections), can realize efficient reliable without using couplings at all. All employed expressions diabatic Hamiltonian matrix elements be flexibly set input files. mainly written Fortran based modular design has great capacity further implementation methods. used simulate both model atomistic as long proper provided. As demonstrations, series representative models studied show main features capabilities.

Язык: Английский

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Nonadiabatic Field: A Conceptually Novel Approach for Nonadiabatic Quantum Molecular Dynamics

Journal of Chemical Theory and Computation, Год журнала: 2025, Номер unknown

Опубликована: Апрель 7, 2025

Reliable trajectory-based nonadiabatic quantum dynamics methods at the atomic/molecular level are critical for practical understanding and rational design of many important processes in real large/complex systems, where dynamical behavior electrons that nuclei coupled. The paper reports latest progress field (NaF), a conceptually novel approach with independent trajectories. Substantially different from mainstreams Ehrenfest-like surface hopping methods, nuclear force NaF involves arising coupling between electronic states, addition to adiabatic contributed by single state. is capable faithfully describing interplay motion broad regime, which covers relevant states keep coupled wide range or all time bifurcation characteristic essential. derived exact generalized phase space formulation coordinate-momentum variables, constraint (CPS) employed discrete electronic-state degrees freedom (DOFs) infinite Wigner used continuous DOFs. We propose efficient integrators equations both diabatic representations. Since formalism CPS not unique, can principle be implemented various representations correlation function (TCF) time-dependent property. They applied suite representative gas-phase condensed-phase benchmark models numerically results available comparison. It shown relatively insensitive representation TCF will potential tool reliable simulations mechanical transition systems.

Язык: Английский

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Unsupervised Machine Learning in the Analysis of Nonadiabatic Molecular Dynamics Simulation

The Journal of Physical Chemistry Letters, Год журнала: 2024, Номер unknown, С. 9601 - 9619

Опубликована: Сен. 13, 2024

The all-atomic full-dimensional-level simulations of nonadiabatic molecular dynamics (NAMD) in large realistic systems has received high research interest recent years. However, such NAMD normally generate an enormous amount time-dependent high-dimensional data, leading to a significant challenge result analyses. Based on unsupervised machine learning (ML) methods, considerable efforts were devoted developing novel and easy-to-use analysis tools for the identification photoinduced reaction channels comprehensive understanding complicated motions simulations. Here, we tried survey advances this field, particularly focus how use ML methods analyze trajectory-based simulation results. Our purpose is offer discussion several essential components protocol, including selection construction descriptors, establishment analytical frameworks, their advantages limitations, persistent challenges.

Язык: Английский

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Coupled-trajectory surface hopping with sign consistency

The Journal of Chemical Physics, Год журнала: 2025, Номер 162(16)

Опубликована: Апрель 22, 2025

The framework of exact factorization (XF) has inspired a series trajectory-based nonadiabatic dynamics methods by introducing different approximations. Recently, the coupled-trajectory surface hopping (CTSH) method been proposed to combine key advantages mixed quantum–classical based on XF and fewest switches hopping. We here present novel variant CTSH, namely, sign-consistent CTSH (SC-CTSH), which considers proper trajectory clustering reconstruct nuclear density distribution consistency between wave function active states introduce decoherence. Using quantum solutions as references, high performance SC-CTSH is benchmarked in widely studied scattering models compared with other related XF-based methods. Due incorporation new sign algorithms, obtains more accurate momentum decoherence during dynamics, makes combination consistent reliable. This study further highlights significance internal states, important development

Язык: Английский

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Large-Scale Non-Adiabatic Dynamics Simulation Based on Machine Learning Hamiltonian and Force Field: The Case of Charge Transport in Monolayer MoS₂

The Journal of Physical Chemistry Letters, Год журнала: 2025, Номер unknown, С. 4907 - 4920

Опубликована: Май 9, 2025

We present an efficient and reliable large-scale non-adiabatic dynamics simulation method based on machine learning Hamiltonian force field. The quasi-diabatic network (DHNet) is trained in the Wannier basis well-designed translation rotation invariant structural descriptors, which can effectively capture both local nonlocal environmental information. Using representative two-dimensional transition metal dichalcogenide MoS2 as illustration, we show that density functional theory (DFT) calculations of only ten structures are sufficient to generate training set for DHNet due high efficiency analysis orbital classification sampling interorbital couplings. demonstrates good transferability, thus enabling direct construction electronic matrices large systems. Compared with DFT calculations, significantly reduces computational cost by about 5 orders magnitude. By combining DeePMD field, successfully simulate electron transport monolayer up 3675 atoms 13475 levels using a state-of-the-art surface hopping method. mobility calculated be 110 cm2/(V s), agreement extensive experimental results range 3-200 s) during 2013-2023. Due performance, proposed methods have great potential applied study charge carrier wide material

Язык: Английский

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Essential challenges and new opportunities in the investigation of excited state structure and dynamics for complex systems

Scientia Sinica Chimica, Год журнала: 2024, Номер 54(12), С. 2348 - 2360

Опубликована: Июль 25, 2024

Язык: Английский

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Multiconfigurational Surface Hopping: a Time-Dependent Variational Approach with Momentum-Jump Trajectories

Journal of Chemical Theory and Computation, Год журнала: 2024, Номер unknown

Опубликована: Авг. 31, 2024

The Ehrenfest mean field dynamics and trajectory surface hopping have been widely used in nonadiabatic simulations. Based on the time-dependent variational principle (TDVP), multiconfigurational (MCE) method has also developed can be regarded as a extension of traditional dynamics. However, it is not straightforward to apply TDVP trajectories because there exists momentum jump during hops. To solve this problem, we here propose (MCSH) method, where continuous momenta are obtained by linear interpolation interpolated construct basis functions for postprocessing manner. As demonstrated series representative spin-boson models, MCSH achieves high accuracy with only several hundred bases uniformly improve performance hopping. In principle, combined all kinds mixed quantum-classical thus potential properly describe general

Язык: Английский

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