Karlsruhe Institute of Technology, KIT Campus South, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany.
Inorg Chem. 2013 Mar 4;52(5):2292-305. doi: 10.1021/ic300979c. Epub 2012 Oct 12.
A series of highly luminescent dinuclear copper(I) complexes has been synthesized in good yields using a modular ligand system of easily accessible diphenylphosphinopyridine-type P^N ligands. Characterization of these complexes via X-ray crystallographic studies and elemental analysis revealed a dinuclear complex structure with a butterfly-shaped metal-halide core. The complexes feature emission covering the visible spectrum from blue to red together with high quantum yields up to 96%. Density functional theory calculations show that the HOMO consists mainly of orbitals of both the metal core and the bridging halides, while the LUMO resides dominantly on the heterocyclic part of the P^N ligands. Therefore, modification of the heterocyclic moiety of the bridging ligand allows for systematic tuning of the luminescence wavelength. By increasing the aromatic system of the N-heterocycle or through functionalization of the pyridyl moiety, complexes with emission maxima from 481 to 713 nm are obtained. For a representative compound, it is shown that the ambient-temperature emission can be assigned as a thermally activated delayed fluorescence, featuring an attractively short emission decay time of only 6.5 μs at ϕPL = 0.8. It is proposed to apply these compounds for singlet harvesting in OLEDs.
一系列高发光的双核铜（I）配合物已通过使用易于获得的二苯基膦吡啶型 P^N 配体的模块化配体系统以良好的产率合成。通过 X 射线晶体学研究和元素分析对这些配合物进行的表征揭示了具有蝴蝶形金属卤化物核的双核配合物结构。这些配合物的发射涵盖了从蓝色到红色的可见光谱，同时具有高达 96%的高量子产率。密度泛函理论计算表明，HOMO 主要由金属核和桥连卤化物的轨道组成，而 LUMO 主要位于 P^N 配体的杂环部分上。因此，桥连配体的杂环部分的修饰允许对发光波长进行系统调谐。通过增加 N-杂环的芳香体系或通过吡啶部分的官能化，可以获得发射最大值从 481nm 到 713nm 的配合物。对于代表性化合物，表明环境温度下的发射可归因于热激活延迟荧光，其发射衰减时间仅为 6.5μs，在 ϕPL = 0.8 时。提议将这些化合物应用于 OLED 中的单线态捕获。
