A New Strategy of Design and Development of Aggregation-Induced Emission Materials Based on a Deep Insight into Mechanism

It is of great significance to explore the mechanism of aggregation-induced emission (AIE) process for the design and development of AIEgens. Based on the systematic investigation of the absorption and emission spectra of 1,1,2,2- tetraphenylethene(TPE), Pyrene, and 1-[4-(1,2,2-Triphenylethenyl)phenyl]pyrene (TPEpy), we found that (1) the rotation of aromatic substituents and the π-π stacking interactions are the dominant pathways for the non-radiation decay of AIEgens; (2) the rotation barrier of aromatic substituents at the excited state is more reliable than at the ground state and can reliably predict the fluorescence effects of AIEgens; (3) the higher rotation barriers at the excited state of aromatic substituents for TPEpy compared with that of TPE indicate that the fluorescence effect of TPEpy is stronger than that of TPE at the same concentration. This theoretical deduction is consistent with the experimental results. Based on the deep understanding of the AIE mechanism, a new strategy to design a...