Figure: © Jörg Harms, MPSD. In the singlet exciton fission process, a singlet exciton (blue) is created upon absorbing light and then splits into two triplets (red) on ultrafast timescales. We have investigated the structural dynamics accompanying this process.

Singlet exciton fission (SEF) is a process occurring in several organic semiconductors by which an electronically excited singlet exciton spontaneously splits into two triplet excitons. The SEF properties, such as yields and rates, depend crucially on the molecular structure and intermolecular interactions. This calls for an experimental technique that can probe the structural changes accompanying the SEF process at the relevant time and length scales.
In a study published in Science Advances, we [more...]