Projects per year
Abstract
The Gaussian-based multiconfiguration time-dependent Hartree (G-MCTDH) method is applied to calculate the S-2(pi pi(*)) absorption spectrum of the pyrazine molecule, whose diffuse structure results from the ultrafast nonadiabatic dynamics at the S-2-S-1 conical intersection. The 24-mode second-order vibronic-coupling model of Raab [J. Chem. Phys. 110, 936 (1999)] is employed, along with 4-mode and 10-mode reduced-dimensional variants of this model. G-MCTDH can be used either as an all-Gaussian approach or else as a hybrid method using a partitioning into primary modes, treated by conventional MCTDH basis functions, and secondary modes described by Gaussian particles. Comparison with standard MCTDH calculations shows that the method converges to the exact result. The variational, nonclassical evolution of the moving Gaussian basis is a key element in obtaining convergence. For high-dimensional systems, convergence is significantly accelerated if the method is employed as a hybrid scheme.
Original language | English |
---|---|
Pages (from-to) | 174104 |
Number of pages | 1 |
Journal | Journal of Chemical Physics |
Volume | 129 |
Issue number | 17 |
DOIs | |
Publication status | Published - 1 Nov 2008 |
Keywords
- organic compounds
- variational techniques
- ultraviolet spectra
- visible spectra
- vibronic states
- infrared spectra
Fingerprint
Dive into the research topics of 'Multimode quantum dynamics using Gaussian wavepackets: The Gaussian-based multiconfiguration time-dependent Hartree (G-MCTDH) method applied to the absorption spectrum of pyrazine'. Together they form a unique fingerprint.Projects
- 1 Finished
-
CCP6 Renewal: Developing Quantum Dynamics for Large Systems
Worth, G.
Engineering & Physical Science Research Council
12/03/07 → 11/03/10
Project: Research Councils