Dresden 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 22: Organic Electronics and Photovoltaics II (CPP jointly with DS, HL, O)
O 22.10: Talk
Monday, March 31, 2014, 17:45–18:00, ZEU 222
Model systems for interchromophoric interactions in conjugated polymer materials — •Thomas Stangl1, Daniela Schmitz2, Klaas Remmerssen2, Dominik Würsch1, Florian Steiner1, Sigurd Höger2, Jan Vogelsang1, and John Lupton1 — 1Universität Regensburg, Regensburg, Deutschland — 2Universität Bonn, Bonn, Deutschland
A set of pi-conjugated oligomer dimers templated in molecular scaffolds is presented as a model system of the interactions between chromophores in conjugated polymers. Single-molecule spectroscopy was used to reveal electronic aggregation between two oligomers with different well-defined distances and single polymer chains. It is concluded that the model systems can be used to investigate the impact of H-aggregation as a function of interchromophoric distance by simultaneous measurement of lifetime and single-molecule spectra. This reveals a strong heterogeneity in coupling strengths even for identical single molecules. Further, it is shown that the coupling strength varies over time on a single molecule, leading to the conclusion that electronic aggregation has to be understood as a dynamic property. In bulk polymer films, such interchromophoric coupling impacts the functionality, e.g. the emission color and the migration of excitation energy to quenching sites. Realizing the presence and dynamics of such interactions is crucial for understanding limitations in quantum efficiency of larger conjugated polymer materials.