Dual‐State Emission and Two‐Photon Absorption Tuned by Benzonitrile Substitution in 2,3,4,5‐Tetraphenyl‐1H‐Pyrrole

A series of nine 2,3,4,5-tetraphenyl pyrrole derivatives presenting benzonitrile substitution at different positions was designed and synthesized for this work. Their structure–emission property relationships were investigated in depth through a joint advanced experimental computational effort. Our ultrafast non-linear spectroscopic results showed more efficient intramolecular charge transfer enhanced two-photon absorption cross sections when the is position 3 central pyrrole. On other hand, an intriguing dual-state emission behaviour found to be activated by 2, with exceptionally large photoluminescence quantum yields exhibited both solution solid state. Indeed, chemical simulations revealed functionalized 2 that distorted geometry substituent respect phenyl ring prevents quenching aggregate species π-π stacking interactions. findings shed new light on optimized design strategies highly emitting materials optoelectronic devices.