Organic semiconductors are widely used in prominent applications such as organic light‐emitting diode displays and organic solar cells. The state of the art of predictive simulation methods is discussed, including machine learning, to complement experimental research in the identification of novel materials in the vast available chemical space, and their potential is illustrated with a few prominent recent applications.Adv. Mat., DOI: 10.1002/adma.201808256
Nanocrystalline graphene shows significantly different high-temperature behavior compared to pristine graphene. In this work we analyze the dynamics of graphene formation during in situ heating experiments. Therefore, we combine high-throughput transmission electron microscopy and computational modeling to get an insight into fundamental processes. We observe that the reactive nature of unsaturated edges and defects in nanocrystalline graphene enables various temperature-driven rearrangement mechanisms.Nanoscale Adv., DOI: 10.1039/C9NA90036E
The last decades brought a massive development of simulation methods for materials science, chemistry and soft matter applications, now being efficient and accurate for the targeted application area. In this RTG we will systematically investigate problems, which are not addressable by standard tools from the quantum chemistry toolbox. The research is organized into seven projects, where five projects address scientific challenges like friction, materials aging, material design and biological function, which so far cannot be approached by single computational methods or standard multiscale approaches. The challenges are met, (i) by building teams which cover all knowledge and methods required to address scale-bridging problems, (ii) by a research program, which aims at a novel holistic, problem-driven approach to combine existing methods on the individual scales to recursive scale-bridging workflows and (iii) by training doctoral researchers, who are enabled to apply scale-bridging concepts and technical skills needed for such a problem-driven approach.GRK 2450
We are proud to be part of the the new excellence cluster 3D Matter Made to Order (3DMM2O)!
The viability of a multiscale simulation approach to rationally design organic semiconductors with improved electron mobility is demonstrated. Novel materials with tailored electronic properties are designed for which an improvement of the electron mobility by three orders of magnitude is predicted and experimentally confirmed.Adv. Mat, DOI: 10.1002/adma.201703505
Proton‐conducting molecules in the pores of metal–organic frameworks change their conductivity upon photoswitching the host framework. In this work, irradiation with light (green) causes trans–cis isomerization of the azobenzene components of the framework, switching the molecular interaction and the conductivity of the triazole guest molecules (center). The sample is mounted on interdigitated gold electrodes, which are used for measuring the conductivity.Adv. Mat., DOI: 10.1002/adma.201706551
This video illustrates the principle of OLED devices. Electrons and holes are injected at the electrodes, drift through the device and emit light when they recombine. The charge carrier movement in a real device can be simulated using the kinetic Monte-Carlo method, which has been implemented in our group.Video posted on YouTube