Excited state dynamics for hybridized local and charge transfer state fluorescent emitters with aggregation-induced emission in the solid phase: a QM/MM study

) are effectively hindered by the restricted intramolecular rotation (RIR) effect in the solid phase. The fluorescence efficiency of the OLED has been quantitatively calculated. The results show that the fluorescence efficiency is greatly enhanced from 0.16% in the gas phase to 52.1% in the solid phase; this demonstrates the aggregation-induced emission (AIE) mechanism for the OLED. Furthermore, by combining the dynamics of the excited states and the adiabatic energy structures calculated in the solid phase, the so-called hot-exciton process from higher triplet states to a singlet state has been illustrated. Our investigation elucidates the experimental measurement and helps understand the AIE mechanism for HLCT compounds, which is beneficial for developing highly efficient emitters.