Journal ArticleDOI
Multilayer formulation of the multiconfiguration time-dependent Hartree theory
Haobin Wang,Michael Thoss +1 more
TLDR
In this paper, a multilayer formulation of the multiconfiguration time-dependent Hartree (MCTDH) theory is presented, where the single-particle (SP) functions in the original MCTDH method are further expressed employing a timedependent multi-figurational expansion, and the Dirac-Frenkel variational principle is applied to optimally determine the equations of motion.Abstract:
A multilayer (ML) formulation of the multiconfiguration time-dependent Hartree (MCTDH) theory is presented. In this new approach, the single-particle (SP) functions in the original MCTDH method are further expressed employing a time-dependent multiconfigurational expansion. The Dirac–Frenkel variational principle is then applied to optimally determine the equations of motion. Following this strategy, the SP groups are built in several layers, where each top layer SP can contain many more Cartesian degrees of freedom than in the previous formulation of the MCTDH method. As a result, the ML-MCTDH method has the capability of treating substantially more physical degrees of freedom than the original MCTDH method, and thus significantly enhances the ability of carrying out quantum dynamical simulations for complex molecular systems. The efficiency of the new formulation is demonstrated by converged quantum dynamical simulations for systems with a few hundred to a thousand degrees of freedom.read more
Citations
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Journal ArticleDOI
The Ultrafast Quantum Dynamics of Photoexcited Adenine-Thymine Basepair Investigated with a Fragment-based Diabatization and a Linear Vibronic Coupling Model.
TL;DR: In this article, a quantum dynamical study of the photoexcited hydrogen bonded base pair adenine-thymine (AT) in a Watson-Crick arrangement was presented, where wavepacket propagations were run with the multilayer extension of the Multiconfiguration Time-Dependent Hartree method.
Journal ArticleDOI
The hierarchy of Davydov's Ansätze: From guesswork to numerically "exact" many-body wave functions.
TL;DR: In this article , the Davydov's Ansätze has been applied to the generalized Holstein Hamiltonian, variants of the spin-boson model, and systems of cavity-assisted singlet fission.
Journal ArticleDOI
Automatic Evolution of Machine-Learning-Based Quantum Dynamics with Uncertainty Analysis.
TL;DR: This study provides an efficient protocol to build optimal neural networks and estimate the trustiness of the machine learning models by employing various hyperparameter optimization methods, including simulated annealing, Bayesian optimization with tree-structured parzen estimator, and random search.
Journal ArticleDOI
Direct nonadiabatic quantum dynamics simulations of the photodissociation of phenol.
TL;DR: In this paper, the Direct Dynamics Variational Multi-Configurational Gaussian (DD-vMCG) method has been used to describe the multidimensional photodissociation dynamics of phenol including all degrees of freedom.
Simulation of condensed gasses by variation of their coherent state expansions
TL;DR: In this paper, it was shown that the fair sampling assumption of the Monte-Carlo methods is essential to represent states of such fields, and that this method, it its current form, can not simulate the dynamics of fields with high-dimensional classical phase spaces.
References
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Journal ArticleDOI
Light-Induced Redox Reactions in Nanocrystalline Systems
Anders Hagfeldt,Michael Graetzel +1 more
TL;DR: A review with 156 refs on interfacial electron transfer reactions in colloidal semiconductor solns and thin films and their application for solar light energy conversion and photocatalytic water purifn is presented in this paper.
Journal ArticleDOI
Dynamics of the dissipative two-state system
Anthony J. Leggett,Sudip Chakravarty,Alan T. Dorsey,Matthew P. A. Fisher,Anupam Garg,Wilhelm Zwerger +5 more
TL;DR: In this article, a functional-integral approach to the dynamics of a two-state system coupled to a dissipative environment is presented, and an exact and general prescription for the reduction, under appropriate circumstances, of the problem of a system tunneling between two wells in the presence of dissipative environments to the spin-boson problem is given.
Book
Quantum Dissipative Systems
TL;DR: In this paper, the authors present a survey of the various approaches to Quantum-Statistical metastability, including Imaginary-Time and Real-Time Approaches Influence Functional Method Phenomenological and Microscopic System-Plus-Reservoir Models Linear and Nonlinear Quantum Environments Ohmic, Super-Ohmic, and Sub-ohmic Dissipation Quantum Decoherence and Relaxation Correlation Functions, Response Functions, and Fluctuation-Dissipation Theorem Damped Quantum Mechanical Harmonic Oscillator Quantum Brownian Motion Thermodynamic Variational
Journal ArticleDOI
The multiconfiguration time-dependent Hartree (MCTDH) method: a highly efficient algorithm for propagating wavepackets
TL;DR: In this article, a review of the multiconfiguration time-dependent Hartree (MCTDH) method for propagating wavepackets is given, and the formal derivation, numerical implementation, and performance of the method are detailed.
Journal ArticleDOI
Trajectory Surface Hopping Approach to Nonadiabatic Molecular Collisions: The Reaction of H+ with D2
John C. Tully,Richard K. Preston +1 more
TL;DR: In this article, an extension of the classical trajectory approach is proposed that may be useful in treating many types of nonadiabatic molecular collisions, where nuclei are assumed to move classically on a single potential energy surface until an avoided surface crossing or other region of large NDE coupling is reached.