A group of new iridium(III) complexes were rationally designed and synthesized with 2-phenylbenzo[d]oxazole (bo), 2-phenylbenzo[d]thiazole (bt), 2-(thiophen-2-yl)benzo[d]thiazole (thbt), and 2-(selenophen-2-yl)benzo[d]thiazole (sebt) as C^N ligands and bis(diphenylthiophosphoryl)amide (S-tpip) as ancillary ligand. They are phosphorescent in a wide region of green to red with short lifetimes around 0.31–0.98 μs and quantum yields up to 64.7%. The detailed photophysical properties were investigated by experiment and further supported by density functional theory (DFT) calculation. These research results show that the spectroscopic properties are tuned by the replacement between oxygen, sulfur, and selenium or the change in aromatic ring. It has been demonstrated that the lowest energy-level absorption and emission are dominated apparently by C^N ligands, and are ascribed to metal-to-ligand charge transfer (MLCT) and intra-ligand charge transfer (ILCT) characters.

中文翻译：

---

含 O、S 和 Se 杂原子的 C^N 配体对四种磷光 Ir(III) 配合物颜色调节的影响

以2-苯基苯并[d]恶唑(bo)、2-苯基苯并[d]噻唑(bt)、2-(噻吩-2-基)苯并[d]合理设计合成了一组新型铱(III)配合物噻唑（thbt）和2-（硒酚-2-基）苯并[d]噻唑（sebt）作为C^N配体，双（二苯基硫代磷酰基）酰胺（S-tpip）作为辅助配体。它们在绿色到红色的宽范围内发出磷光，寿命较短，约为 0.31–0.98 μs，量子产率高达 64.7%。通过实验研究了详细的光物理性质，并通过密度泛函理论（DFT）计算进一步支持。这些研究结果表明，光谱性质是通过氧、硫和硒之间的置换或芳环的变化来调节的。研究表明，最低能级的吸收和发射明显由C^N配体主导，并归因于金属配体电荷转移（MLCT）和配体内电荷转移（ILCT）特征。