Two biphenyl diimide (BPI) monomers containing seven‐membered imide rings and four conjugated aromatic diimides, BPI‐Ph, BPI‐Th, BPI‐Se and BPI‐Py, with unique aggregation‐induced blue‐shifted emission (AIBSE) properties, are reported. The crystal structures revealed that the imide backbones were twisted, leading to weaker 1D π‐stacking, which makes the compounds very different from other reported imides. Their cyclic voltammetry, UV/Vis absorption and fluorescence spectra, as well as DFT calculations, were investigated in detail. The photophysical properties and aggregation behaviors of BPI‐Ph, BPI‐Th, BPI‐Se and BPI‐Py in mixtures of THF/water were systematically studied. The intriguing AIBSE of the BPI‐containing compound was attributed to the lower reorganization energies in aggregates than in the solution phase, ascribed to the lack of π‐stacking resulting from the twisted seven‐membered rings, restricted intramolecular rotation (RIR) and weak intermolecular interactions in the solid state. Additionally, BPI‐Py‐based OLEDs exhibited good performance of L_max, η_C,_max, η_P,_max and η_ext,_max up to 6014 cd m⁻², 6.41 cd A⁻¹, 5.50 lm W⁻¹ and 3.85 %, respectively. The presented results provide a new strategy to design blue emitters in the future.

中文翻译：

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基于联苯二酰亚胺的新型蓝色发射体，具有聚集诱导的蓝移发射特性

含有七个七元酰亚胺环和四个共轭芳族二酰亚胺的两个联苯二酰亚胺（BPI）单体BPI-Ph，BPI-Th，BPI-Se和BPI-Py具有独特的聚集诱导的蓝移发射（AIBSE）特性。报告。晶体结构表明酰亚胺主链被扭曲，导致较弱的一维π-堆积，这使得该化合物与其他报道的酰亚胺大不相同。详细研究了它们的循环伏安法，UV / Vis吸收和荧光光谱以及DFT计算。系统研究了BPI-Ph，BPI-Th，BPI-Se和BPI-Py在THF /水混合物中的光物理性质和聚集行为。含BPI的化合物有趣的AIBSE归因于聚集体中的重组能比溶液相中的重组能低，归因于固态七元环扭曲，分子内旋转受限（RIR）和分子间相互作用弱导致π堆积不足。此外，基于BPI-Py的OLED表现出良好的性能大号_最大值，η _Ç，_最大值，η _P，_最大和η _EXT，_最高可达6014 CD米^-2，6.41光盘^-1，5.50流明w ^ ^-1和分别3.85％。提出的结果为将来设计蓝色发射器提供了新的策略。