Unravelling the Superiority of Nonbenzenoid Acepleiadylene as a Building Block for Organic Semiconducting Materials**

Abstract

Acepleiadylene (APD), a nonbenzenoid isomer of pyrene, exhibits a unique charge‐separated character with a large molecular dipole and a small optical gap. However, APD has never been explored in optoelectronic materials to take advantage of these appealing properties. Here, we employ APD as a building block in organic semiconducting materials for the first time, and unravel the superiority of nonbenzenoid APD in electronic applications. We have synthesized an APD derivative (APD‐IID) with APD as the terminal donor moieties and isoindigo (IID) as the acceptor core. Theoretical and experimental investigations reveal that APD‐IID has an obvious charge‐separated structure and enhanced intermolecular interactions as compared with its pyrene‐based isomers. As a result, APD‐IID displays significantly higher hole mobilities than those of the pyrene‐based counterparts. These results imply the advantages of employing APD in semiconducting materials and great potential of nonbenzenoid polycyclic arenes for optoelectronic applications.