Organic luminescent crystals: role of packing structures and optical properties

Solid-state luminescence of organic & pi;-conjugated molecules has become an international cutting-edge research area in recent years. Theoretical studies reveal that the optical properties in the aggregate state are closely related to the interactions between the transition dipoles of adjacent molecules. Therefore, manipulating the intermolecular interactions and stacking modes can efficiently modulate the luminescent properties of organic crystals. Herein, we review recent studies focused on understanding the role of molecular packing structures and optical properties in & pi;-conjugated organic luminescent crystals. Additionally, the various applications of stimuli response, as well as amplified spontaneous emission and organic solid-state laser, are also presented. Moreover, the development and future prospects of this research field are proposed. This review provides an in-depth understanding of the molecular structure-property relationship, which can guide the specific design of organic luminescent molecules with desirable optoelectronic properties in the aggregate states.