Principal Investigator Adam Willard
Molecular semiconducting materials are comprised of many individual molecules whose individual electronic properties combine to yeild material-wide semiconducting properties. Unlike traditional crystalline semiconductors, the electronic structure of these materials is often spatially and temporally heterogeneous due to the relatively weak van der Waals forces that drive molecular association. Predicting how this heterogeneity affects the electronic properties of these materials is a significant theoretical challenge because the characteristic length scales involved are beyond the capabilities of most quantum chemistry techniques.
Research combines methods of statistical mechanics and quantum dynamics in order to explore how nanoscale disorder affects the emergent electronic properties in molecular semiconducting materials. This relationship is mediated by the static and dynamic properties of excitons, Coulombically bound excited electron-hole pairs. These energetic quasiparticles mediate molecular-scale energy transport in a wide range of systems ranging from modern organic light-emitting diodes (OLEDs) to the light-harvesting machinery in photosynthetic systems. The approach is focused on developing models that describe the subtle dependence of electronic structure on molecular configuration while simultaneously accounting for the nanoscale correlations that arise through collective molecular fluctuations.