Theory of Conducting Organic Polymers

Conducting organic polymers (COP)s are pi-conjugated systems (see some examples below) which combine the properties of plastics which those of metals or semi-conductors. After their discovery, the focus was on their electrical properties for usage as molecular wires or materials for batteries. It turned out that the optical properties of conjugated systems, like electrochromism and light absorption are more useful and extensive research is carried out currently on light harvesting systems, light emmitting diodes, and organic fiels effect transistors.
Polymers may have high molecular weight but short conjugation lengths due to disorder. Therefore polymers are hard to characterize. Because polymer properties develop gradually from oligomer properties with increasing chain length, disordered polymers behave more like medium-sized oligomers. Theoretical studies on medium to large-size oligomers can therefore model experiments realistically and provide valuable insights on chain lengths effects.
My interests focus on theoretical investigation of absorption and photoelectron spectra of homo- and donor-acceptor oligomers, on the nature of the charge carriers in COPs, and on intramolecular singlet fission. The main theoretical tools are density functional theory and high level ab initio methods where possible.