All-DFTB Approach to the Parametrization of the System-Bath Hamiltonian Describing Exciton-Vibrational Dynamics of Molecular Assemblies
- Spectral density functions are central to the simulation of complex many body systems. Their determination requires making approximations not only to the dynamics but also to the underlying electronic structure theory. Here, blending different methods bears the danger of an inconsistent description. To solve this issue we propose an all-DFTB approach to determine spectral densities for the description of Frenkel excitons in molecular assemblies. The protocol is illustrated for a model of a PTCDI crystal, which involves the calculation of monomeric excitation energies and Coulomb couplings between monomer transitions, as well as their spectral distributions due to thermal fluctuations of the nuclei. Using dynamically defined normal modes, a mapping onto the standard harmonic oscillator spectral densities is achieved.
| Author details: | Per-Arno PlötzORCiDGND, Jörg MegowGND, Thomas NiehausORCiD, Oliver KühnORCiDGND |
|---|---|
| DOI: | https://doi.org/10.1021/acs.jctc.8b00493 |
| ISSN: | 1549-9618 |
| ISSN: | 1549-9626 |
| Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/30141929 |
| Title of parent work (English): | Journal of chemical theory and computation |
| Publisher: | American Chemical Society |
| Place of publishing: | Washington |
| Publication type: | Article |
| Language: | English |
| Date of first publication: | 2018/10/09 |
| Publication year: | 2018 |
| Release date: | 2021/09/21 |
| Volume: | 14 |
| Issue: | 10 |
| Number of pages: | 10 |
| First page: | 5001 |
| Last Page: | 5010 |
| Funding institution: | Deutsche ForschungsgemeinschaftGerman Research Foundation (DFG) [ME 4215/2-3, Sfb 652] |
| Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
| DDC classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
| Peer review: | Referiert |
| Publishing method: | Open Access / Green Open-Access |
