Calculation of Electronic Structure and Transport properties of Donor – Acceptor Polymers


Calculation of Electronic Structure and Transport properties of Donor – Acceptor Polymers

Günther, F.; Gemming, S.; Seifert, G.

Donor-acceptor (DA) polymers have been found to be good materials for organic electronics since they provide interesting features like mechanical flexibility and high impact resistance.
Moreover, they offer the possibility to produce devises by low cost roll-to-roll printing techniques.
Thus, they are highly promising candidates for organic thin-film transistors and solar cells.
For applications, however, these materials should fulfill several demands such as ambient stability, good solubility, and good film-forming properties.
The charge carrier mobility is one of the most important quantities.
In order to analyse the influence of the molecular structure on these properties, we investigate DA polymers using first-principals methods as density functional theory (DFT).
In particular, density functional based tight binding (DFTB) is used to study large systems.

In our study we analyse the electronic structures of the isolated monomers which are the building blocks of the DA polymers, of finite oligomers up to a length of 20 conjugated units, and of infinite long polymers using periodic boundary conditions.
Furthermore, we investigate the morphological properties by studying systems of several polymer chains with different crossing angles and relative shifts.

Using Marcus transfer theory, we then calculated the electronic transport properties based on hopping processes.
Here, we focus on the coupling matrix elements and their dependence on the stacking configuration.
Using a Boltzmann-like approach for evaluating an average value of this quantity, we obtain good agreements to experimental trends.
Especially the dominating transport type is nicely reproduced by our approach.

  • Lecture (others)
    Arbeitsgruppenseminar der Professur für Theoretische Chemie, 20.11.2014, Dresden, Deutschland
  • Lecture (others)
    Seminar der Professur Theorie ungeordneter Systeme, 17.12.2014, Chemnitz, Deutschland

Permalink: https://www.hzdr.de/publications/Publ-21487
Publ.-Id: 21487