以噻吩苯基喹啉为主配体的铱(Ⅲ)配合物磷光性能的理论研究

Theoretical study on the phosphorescent properties of iridium(Ⅲ) complexes with thiophene-phenylquinoline as main ligand

采用密度泛函理论和二次响应含时密度泛函理论的方法,研究了以噻吩苯基喹啉为主配体的两种磷光铱(Ⅲ)配合物的磷光性能.其中一个是实验已报道配合物,能发出红色磷光;另一个是将次配体替换为1,3,4-噁二唑衍生物后新设计的配合物.从计算的磷光光谱可看出,新设计的配合物比实验配合物的光谱红移了31 nm,是潜在的深红色磷光材料.进而用定量的方法计算了辐射跃迁速率常数,用定性的方法预测了非辐射跃迁速率常数.预测非辐射跃迁速率常数时不仅考虑了与温度无关的非辐射跃迁,也考虑了与温度有关的非辐射跃迁.结果表明,新设计的铱(Ⅲ)配合物的辐射跃迁速率常数和非辐射跃迁速率常数都比实验配合物的大.

By using density functional theory and quadratic response time-dependent density functional theory calculations, the phosphorescent properties of two Ir（Ⅲ） complexes with thiophene-phenylquinoline as the main ligand were investigated. One of complexes, as a reported complex, can emit red phosphorescence, and another is a novelly designed complex with 1,3,4-oxadiazol derivertive as ancillary ligand. Calculated phosphorescent spectrum of the novelly designed complex shifts 31 nm to red compared with the known one. It s a potential deep red emitting phosphorescent complex. Then the radiative rate constant was quantitatively determined, while the nonradiative decay rate was qualitatively evaluated both by temperature-independent and temperature-dependent nonradiative decay processes. It shows that both the radiative decay rate constant and the nonadiative decay rate constant of the newly designed complex are larger than those of the known complex.