Photophysical properties of ligand localized excited state in ruthenium(ii) polypyridyl complexes: a combined effect of electron donor–acceptor ligand
作者:Sandeep Verma、Prasenjit Kar、Amitava Das、Hirendra Nath Ghosh
DOI:10.1039/c1dt10266d
日期:——
the 3MLCT state by the low-emissive 3LLCT state. The emission due to ligand localized CT state (ILCT and LLCT) of complexes 2 and 3 is revealed at 77 K in the form of a new luminescence band which appeared in the 670–760 nm region. The LLCT excited state of complex 3 is populated either via direct photoexcitation in the LLCT absorption band (350–700 nm) or through internal conversion from the photoexcited
我们已经合成 钌(II)聚吡啶基配合物(1)Ru(II)(bpy)2(L 1),(2)Ru(II)(bpy)2(L 2)和(3)Ru(II)(bpy)(L 1)(L 2), 在哪里 py = 2,2'-联吡啶,L 1 =4- [2-(4'-甲基-2,2'-联吡啶基-4-基)乙烯基]苯-1,2-二醇)和L 2 =4-(N,N-二甲基氨基-苯基)-(2,2'-联吡啶)通过光吸收和发射研究,研究了配体内电荷转移(ILCT)和配体-配体电荷转移(LLCT)状态。我们的研究表明,L 2中存在给电子-NMe 2官能团和吸电子儿茶酚复合物3的L 1配体中的片段将低能量LLCT激发态引入到原代MLCT态。与配合物1和2相比,叠加的LLCT和MLCT状态在配合物3的光吸收光谱中产生红移和加宽。与配合物1和2在室温下相比,观察到配合物3的发射量子产率极低。这归因于低发射3 LLCT状态对3 MLCT状态的淬灭