CALCULATION OF INTER-MOLECULAR TRANSITION RATES DEPENDING ON STRUCTURAL PARAMETERS

Robin Silligmann; Florian Günther; Fabian Teicher; Angela Thränhardt

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Submission

Paper Title

CALCULATION OF INTER-MOLECULAR TRANSITION RATES DEPENDING ON STRUCTURAL PARAMETERS

Authors

Robin Silligmann
Florian Günther
Fabian Teicher
Angela Thränhardt

Modality

Pôster

Subject area

Simulação computacional / Teoria

Publishing Date

12/12/2023

Country of Publishing

Brasil

Language of Publishing

Inglês

Paper Page

https://www.even3.com.br/anais/workshop-do-ineo-2023/613262-calculation-of-inter-molecular-transition-rates-depending-on-structural-parameters

ISBN

978-65-272-0088-8

Keywords

electronic transport, transition rates, marcus transfer, density functional based tight binding

Summary

Organic semiconductors become increasingly important for electronic applications. The large number of organic materials and their combinations make it useful to investigate properties like current-voltage characteristics, by means of simulations in order to find suitable material combinations for applications. This is usually done via Monte-Carlo hopping simulations, which can be used to describe the large-scale transport of charges within organic materials. Such models, however, require the knowledge of transfer rates and morphologies which in turn exhibit the actual dependence on the molecular structure. Hence, a detailed knowledge on the inter-molecular interactions is required, before modeling actual device properties. In our work, we focus on the calculation of the transition rates of electrons between two organic molecules, and especially their dependence on structural fluctuations. For this, we calculate HOMO and LUMO states, reorganization energies and Hamiltonian coupling elements. Based on these parameters, the transition rates can be computed using Marcus transfer theory. In order to densely sample possible structural variations, computationally efficient approach is required. For this, the density functional based tight binding (DFTB) method is well suited, as it allows fast computation of electronic structure properties without much empirical assumption. The final goal of our work is to characterize statistical distribution of the transition rate determining parameter. These can later on be directly incorporated in the Monte-Carlo hopping simulations. In this contribution, we are going to present results for three systems: (1) single thiophene rings (2) a zinc-porphyrin derivative functionalized with thiophene and diketo-pyrrolopyrrole units (ZnPor), and (3) phenyl-C61-butyric acid methyl ester (PC61BM). While we use thiophene as reference to compare our implementation to other work, ZnPor:PCBM systems have been reported as promising candidates for organic solar cells and are therefore interesting to be studied. We show the obtained distributions of reorganization energies, of Hamiltonian coupling constants and finally of the individual transition rates for different molecular arrangements.

Title of the Event: Workshop do INEO 2023
City of the Event: Nazaré Paulista
Title of the Proceedings of the event: Anais do Workshop INEO 2023
Name of the Publisher: Even3
Means of Dissemination: Meio Digital

How to cite

SILLIGMANN, Robin et al.. CALCULATION OF INTER-MOLECULAR TRANSITION RATES DEPENDING ON STRUCTURAL PARAMETERS.. In: Anais do workshop INEO 2023. Anais...Nazaré Paulista(SP) Hotel Estância Atibainha, 2023. Available in: https//www.even3.com.br/anais/workshop-do-ineo-2023/613262-CALCULATION-OF-INTER-MOLECULAR-TRANSITION-RATES-DEPENDING-ON-STRUCTURAL-PARAMETERS. Access in: 23/04/2025