High Exciton Utilization of 1D Molecular Column with High Packing Energy Formed by Folded p-Molecules

Abstract

π-Molecules play important roles in many applications such as organic light-emitting devices, photocatalysis, photovoltaics, biosensors, and medicine. Very often, π-conjugated molecules with high utilization of excited states in the solid state are of great research interest. However, owing to the gap between molecular structure and effective molecular packing, there are very few designs toward πmolecules with very high exciton utilization in the solid state. Herein, we report a new πskeleton, folded π, to achieve high exciton utilization in the solid state. Based on a "folded π"formula, 12 compounds with two or three folding πplanes were designed and synthesized. We found that folded πmolecules tend to form well-aligned 1D molecular columns of patterns ("box", "braid", or "stair") with high packing energy, which is mainly contributed by numerous weak πinteractions. As a result of effective suppression of molecular motion, all the compounds show very high exciton utilization in solids.