Ikeda Ko, Yano Natsumi, Handa Makoto, Kataoka Yusuke
Department of Chemistry, Graduate School of Natural Science and Technology, Shimane University, 1060, Nishikawatsu, Matsue 690-8504, Shimane, Japan.
Molecules. 2025 Jan 6;30(1):193. doi: 10.3390/molecules30010193.
A series of luminescent bis-cyclometalated iridium complexes with 2,2':6',2″-terpyridine (tpy), [Ir()(tpy)]PF ( = 2-phenylpyridinate (ppy) for ; benzo[h]quinolinate (bzq) for ; 1-phenylisoquinolinate (piq) for ; and 2-phenylbenzothiazolate (pbt) for ), have been synthesized and structurally characterized. Single-crystal X-ray diffraction analyses reveal that the tpy ligands of - are coordinated to the iridium center in a bidentate fashion, and the uncoordinated pendant pyridine rings in the tpy ligands of - form intramolecular π-π stacking interactions with a phenyl moiety of ligands. In addition, the pendant pyridine ring in the tpy ligand of forms an intramolecular hydrogen bonding interaction, unlike in -. Of interest, the photophysical properties of - are strongly influenced by the ligands; shows a luminescence band at 572 nm, with a short lifetime (τ) value of 80 nsec and a lower absolute luminescence quantum yield (Φ) of 3.72%, whereas exhibits an intense luminescence band at 588 nm with a long τ value of 1965 nsec and a moderate Φ value of 9.57%. The density functional theory calculations revealed that the luminescence originates from the triplet metal-ligand to ligand charge transfer (MLL'CT) excited state.
一系列含有2,2':6',2″-三联吡啶（tpy）的发光双环金属化铱配合物[Ir()(tpy)]PF（其中 = 2-苯基吡啶（ppy）用于 ；苯并[h]喹啉（bzq）用于 ；1-苯基异喹啉（piq）用于 ；2-苯基苯并噻唑（pbt）用于 ）已被合成并进行了结构表征。单晶X射线衍射分析表明， - 的tpy配体以双齿方式与铱中心配位，并且 - 的tpy配体中未配位的吡啶环与 配体的苯基部分形成分子内π-π堆积相互作用。此外， 中tpy配体的吡啶环形成分子内氢键相互作用，这与 - 不同。有趣的是， - 的光物理性质受到 配体的强烈影响； 在572 nm处显示发光带，具有80纳秒的短寿命（τ）值和3.72%的较低绝对发光量子产率（Φ），而 在588 nm处表现出强烈的发光带以及1965纳秒的长τ值和9.57%的中等Φ值。密度泛函理论计算表明，发光源于三重态金属-配体到配体电荷转移（MLL'CT）激发态。
