Multilayer multiconfiguration time-dependent Hartree method

• Verfasst von: Vendrell, Oriol [VerfasserIn]
• Verfasst von: Meyer, Hans-Dieter [VerfasserIn]
• Titel: Multilayer multiconfiguration time-dependent Hartree method
• Titelzusatz: implementation and applications to a Henon-Heiles Hamiltonian and to pyrazine
• Verf.angabe: Oriol Vendrell and Hans-Dieter Meyer
• E-Jahr: 2011
• Jahr: 28 January 2011
• Umfang: 16 S.
• Fussnoten: Gesehen am 07.12.2022
• Titel Quelle: Enthalten in: The journal of chemical physics
• Ort Quelle: Melville, NY : American Institute of Physics, 1933
• Jahr Quelle: 2011
• Band/Heft Quelle: 134(2011), 4, Artikel-ID 044135, Seite 1-16
• ISSN Quelle: 1089-7690
• DOI: doi:10.1063/1.3535541
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1826465464

Abstract

The multilayer multiconfiguration time-dependent Hartree (ML-MCTDH) method is discussed and a fully general implementation for any number of layers based on the recursive ML-MCTDH algorithm given by Manthe [J. Chem. Phys. 128, 164116 (2008)] is presented. The method is applied first to a generalized Henon-Heiles (HH) Hamiltonian. For 6D HH the overhead of ML-MCTDH makes the method slower than MCTDH, but for 18D HH ML-MCTDH starts to be competitive. We report as well 1458D simulations of the HH Hamiltonian using a seven-layer scheme. The photoabsorption spectrum of pyrazine computed with the 24D Hamiltonian of Raab et al. [J. Chem. Phys. 110, 936 (1999)] provides a realistic molecular test case for the method. Quick and small ML-MCTDH calculations needing a fraction of the time and resources of reference MCTDH calculations provide already spectra with all the correct features. Accepting slightly larger deviations, the calculation can be accelerated to take only 7 min. When pushing the method toward convergence, results of similar quality than the best available MCTDH benchmark, which is based on a wavepacket with - 4.6× - 10 - 7 - 4.6×107 - time-dependent coefficients, are obtained with a much more compact wavefunction consisting of only - 4.5× - 10 - 5 - 4.5×105 - coefficients and requiring a shorter computation time.