Spectral densities for Frenkel exciton dynamics in molecular crystals
- Effects of thermal fluctuations on the electronic excitation energies and intermonomeric Coulomb couplings are investigated for a perylene-tetracarboxylic-diimidecrystal. To this end, time dependent density functional theory based tight binding (TD-DFTB) in the linear response formulation is used in combination with electronic ground state classical molecular dynamics. As a result, a parametrized Frenkel exciton Hamiltonian is obtained, with the effect of exciton-vibrational coupling being described by spectral densities. Employing dynamically defined normal modes, these spectral densities are analyzed in great detail, thus providing insight into the effect of specific intramolecular motions on excitation energies and Coulomb couplings. This distinguishes the present method from approaches using fixed transition densities. The efficiency by which intramolecular contributions to the spectral density can be calculated is a clear advantage of this method as compared with standard TD-DFT. Published by AIP Publishing.
Author details: | Per-Arno PlötzORCiD, Jörg MegowGND, Thomas Niehaus, Oliver KühnORCiDGND |
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DOI: | https://doi.org/10.1063/1.4976625 |
ISSN: | 0021-9606 |
ISSN: | 1089-7690 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/28249454 |
Title of parent work (English): | The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr |
Subtitle (English): | a TD-DFTB approach |
Publisher: | American Institute of Physics |
Place of publishing: | Melville |
Publication type: | Article |
Language: | English |
Date of first publication: | 2017/02/27 |
Publication year: | 2017 |
Release date: | 2022/06/23 |
Volume: | 146 |
Number of pages: | 10 |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
DDC classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Peer review: | Referiert |