研究了6个线性共轭化合物4-丁基联苯(L1)、4,4’-二异丙基联苯(L2)、5,5’-二甲基-2,2’-联吡啶(L3)、2-([1,1’-联苯]-4-)噻吩(L4)、1,1’-联萘(L5)和5-苯基-2,2’-联噻吩(L6)的紫外-可见光谱和荧光发射光谱。结果表明,化合物L1、L2和L3均具有聚集诱导发光(AIE)性能,化合物L4、L5和L6则不具有AIE性能。该研究结果表明,二联苯(或两个简单芳杂环相连)系列化合物具有AIE性能,分子内旋转受限(RIR)是该系化合物产生AIE现象的机理。但是在二联苯的结构基础上继续增加链的长度,或者引入体积更大的芳环(萘环),化合物不再具有AIE性能。
In this article,six linear molecules including 4-butyl-1,1’-biphenyl(L1),4,4’-diisopropyl-1,1’-biphenyl(L2),5,5’-dimethyl-2,2’-bipyridine( L3),2-( [1,1’-biphenyl]-4) thiophene(L4),1,1’-binaphthyl( L5),and 5-phenyl-2,2’-bithiophene( L6) were synthesized. Their luminescent properties were studied by UV-Vis and fluorescence spectra. The results revealed that compound L1,L2 and L3 show AIE properties,while L4,L5,L6 show ACQ properties. We extrapolated that biphenyl-like compounds are AIE active, and restriction of intramolecular rotation( RIR) in the aggregates is the cause for the AIE effect. But linear molecules with more or larger aromatic rings show ACQ phenomena.