Quinoline Substituted Anthracene Isomers: A Case Study for Simultaneously Optimizing High Mobility and Strong Luminescence in Herringbone-Packed Organic Semiconductors

The development of high mobility emissive organic semiconductors is significant for advancing optoelectronic devices with simplified architecture and enhanced performance. The herringbone-packed structure is regarded as the ideal arrangement for simultaneously achieving high mobility and strong emission in organic semiconductors. However, it remains a great challenge that the relationship between molecular structure and optoelectronic property is still elusive. Herein, four quinoline-substituted anthracene isomers were designed and synthesized by introducing quinoline groups to anthracene core. Their intermolecular interactions and packing mode in the herringbone-packed structures were regularly tuning by subtle changing the nitrogen position on quinoline group, resulting in the superior integration of optoelectronic properties. Through a comprehensive analysis of aggregation states and optoelectronic properties, we revealed that in herringbone-packed aggregates, a centroid distance of approximately 7-7.5 Å along CH-π direction and 6-6.5 Å along π-π direction is beneficial for simultaneously achieving high mobility and strong emission. These properties are closely related to the molecular twist angles, which are influenced by intramolecular interactions. This structure-property relationship has been further validated in other herringbone-packed high mobility emissive organic semiconductors, demonstrating its broad applicability and universal potential. This work figures out the practical molecular design principle for high mobility emissive organic semiconductors.