Discrete Heteropolynuclear Yb/Er Assemblies: Switching on Molecular Upconversion Under Mild Conditions
作者:Jie Wang、Yue Jiang、Jiao‐Yang Liu、Hai‐Bing Xu、Yue‐Xing Zhang、Xu Peng、Mohamedally Kurmoo、Seik Weng Ng、Ming‐Hua Zeng
DOI:10.1002/anie.202107637
日期:2021.10.4
hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O-atom serves as a μ2-bridge to two Ln atoms and as a μ3-bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2Er]+), near-infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation
盐 [Ln 2 Ln*(Hhmq) 3 (OAc) 3 (hfac) 2 ] + [Ln*(hfac) 3 (OAc)(MeOH)] - } (Hhmq=2-methanolquinolin-8-oxide, hfac =六氟乙酰丙酮化物;Ln, Ln*=Er, Gd, Yb) 具有由两种镧系元素原子组成的离散杂核阳离子。的喹啉氧基O型原子作为μ 2 -bridge两个LN原子和作为μ 3 -bridge所有三个原子,其中metal⋅⋅⋅metal距离被周围3.7埃。对于1 ( [Yb 2 Er] +),在极低激发功率 (0.288 W cm -2 ) 下,通过引入氟离子,在 980 nm 激光照射下,近红外下移发光转换为竞争性上转换发光。加入氟化物后1的稳定性通过粉末 X 射线衍射和多级质谱法证实,与6 ( [La 2 Eu] + )的1 H NMR相关。更重要的是,在低功率密度(2 W