Highly Emissive H-Aggregates or Aggregation-Induced Emission Quenching? The Photophysics of All-Trans para-Distyrylbenzene

The present Perspective critically re-examines the photophysics of para-distyrylbenzene (DSB) as a prototype of herringbone-arranged H-aggregates to resolve the apparent contradiction of the frequently reported aggregation-induced emission quenching in H-aggregates on one side and highly emissive DSB crystals on the other and discusses the signatures and fate of excitons in single- and polycrystalline samples, including size and polarization effects.