SciPost Submission Page
Non-adiabatic couplings and conversion dynamics between localized and charge transfer excitations from Many-Body Green's Functions Theory
by Gianluca Tirimbo, Björn Baumeier
Submission summary
| Authors (as registered SciPost users): | Bjoern Baumeier |
| Submission information | |
|---|---|
| Preprint Link: | https://doi.org/10.26434/chemrxiv-2023-19ggm (pdf) |
| Code repository: | https://github.com/votca/votca |
| Date submitted: | 2023-01-23 09:09 |
| Submitted by: | Baumeier, Bjoern |
| Submitted to: | SciPost Chemistry Core |
| Ontological classification | |
|---|---|
| Academic field: | Chemistry |
| Specialties: |
|
| Approaches: | Theoretical, Computational |
Abstract
We investigate the determination of non-adiabatic couplings between localized excitations (LEs) and charge-transfer (CT) excitations based on many-body Green's functions theory in the GW approximation with the Bethe--Salpeter equation (GW-BSE). Using a small molecule dimer system, we first study the influence of different diabatization methods, as well as different model choices within GW-BSE, such as the self-energy models or different levels of self-consistency, and find that these choices affect the LE-CT couplings only minimally. We then consider a large-scale low-donor morphology formed from rubrene and fullerene and evaluate the LE-CT couplings based on coupled GW-BSE-molecular mechanics calculations. For these disordered systems of bulky molecules, we observe differences in the couplings based on the Edmiston--Ruedenberg compared to the more approximate Generalize Mulliken--Hush and Fragment Charge Difference diabatization formalisms. In a kinetic model for the conversion between LE and CT states, these differences affect the details of state populations in an intermediate timescale but not the final populations.