Max Planck Institute (MPI-P)

Research into the Transport of Loading and Energy

The Simulation competence center is concerned with research into the mechanisms of the transport of loading and energy in the materials used specifically for organic electronics. In contrast with traditional inorganic semiconductor electronics, in which highly organized physical structures cause strong delocalization effects in charge carriers, thus offering a great amount of conductivity, a weak interaction between the molecules in the physical object are responsible for a strong localization effect on charge carriers in organic electronics. That is why an understanding of the mechanisms of transport of loading and energy at a molecular level is crucial to developing materials with customized properties for applications in organic electronics.

Atomistic Simulation of Transport Processes

The project “Morphology and Electronic Structure of Organics/Organics and Organic/Metal Oxide Hybrid Systems” (MESOMERIE) is being carried out in the Forum Organic Electronics excellence cluster. The atomistic simulation of transport processes is being worked on as part of a sub-project. With a focus on OLEDs, transport and recombination processes in doped film systems will be analyzed in addition to exciton dynamics. The work is intended to create a better understanding of degradation effects in blue OLEDs. The atomistic simulation is broken down into the following individual steps: First, the (usually amorphous) thin film morphologies will be generated. Molecular dynamics, Monte Carlo and coarse graining methods will be applied. Based on these geometries, the quantum chemical transport parameters will be calculated. Finally, transport simulations will be conducted based on the simulated morphologies and the transport parameters calculated which will deliver an image of the loading transport broken down into molecules.

One-Dimensional Drift Diffusion Models

In addition to the atomistic simulation, which is currently limited to one and two film systems, one-dimensional drift diffusion models are also intended for application, which would allow multiple film systems to be simulated. The model equations used are to be adapted based on the transport mechanisms observed in the microscopic simulations.