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
Understanding electronically non-adiabatic relaxation dynamics in singlet fission.
TL;DR: Unlike many other methods, the SQC nondiabatic MD simulation approach is able to describe fission dynamics efficiently and accurately enough to provide microscopic insights into singlet fission.
Journal ArticleDOI
Quantics: A general purpose package for Quantum molecular dynamics simulations
TL;DR: Quantics is a community code of the UK Collaborative Computational Project for Quantum Dynamics (CCPQ) and the European E-CAM project, an e-infrastructure for software development run by the Centre Europeen de Calcul Atomique et Moleculaire (CECAM).
Journal ArticleDOI
Regularity of the multi-configuration time-dependent Hartree approximation in quantum molecular dynamics
Othmar Koch,Christian Lubich +1 more
TL;DR: In this article, a multi-configuration time-dependent Hartree (MCTDH) method was proposed for the approximation of the Schrodinger equation in quantum molecular dynamics, which approximates the high-dimensional nuclear wave function by a linear combination of products of functions depending only on a single degree of freedom.
Journal ArticleDOI
Efficient propagation of the hierarchical equations of motion using the Tucker and hierarchical Tucker tensors
TL;DR: In this article, the Tucker and hierarchical Tucker tensors are used to represent the reduced density operator and auxiliary density operators. And the binary tree structure of the hierarchical equations of motion (HEOM) can be used to propagate a short matrix product state constructed from these nodes.
Journal ArticleDOI
Using an iterative eigensolver and intertwined rank reduction to compute vibrational spectra of molecules with more than a dozen atoms: Uracil and naphthalene
TL;DR: An improvement of the Hierarchical Intertwined Reduced-Rank Block Power Method is introduced that decreases the memory cost of the HI-RRBPM and enables one to compute vibrational spectra of molecules with over a dozen atoms with a typical desktop computer.
References
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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.
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Trajectory Surface Hopping Approach to Nonadiabatic Molecular Collisions: The Reaction of H+ with D2
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