Zhao Ya-Rui, Zheng Hao, Chen Liu-Qing, Chen Hui-Jun, Kong Xiang-Jian, Long La-Sheng, Zheng Lan-Sun
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surface, and Department of Chemistry, College of Chemistry and Chemical Engineering , Xiamen University , Xiamen 361005 , China.
Inorg Chem. 2019 Aug 5;58(15):10078-10083. doi: 10.1021/acs.inorgchem.9b01223. Epub 2019 Jul 24.
Two lanthanide-titanium oxo clusters (LTOCs), formulated as [EuTi(μ-O)(μ-OH)(CHO)(Ac)(CHOH)(tbba)]·CHOH () and [EuTi(μ-O)(μ-OH)(μ-OCH)(μ-OCH)(HO)(CHOH)(tbba)]·Htbba·10HO (), were synthesized through the solvothermal reaction of 4--butylbenzoate ligand, Eu(Ac)·3HO, and Ti(OPr) in methanol. Single-crystal structural analysis reveals that crystallized in the orthorhombic space group 2, and crystallized in the triclinic space group 1. Structurally, the core of can be viewed as a coplanar unit of [EuTi(μ-O)(μ-OH)] formed through each μ-O and μ-OH bridging one Ti and two Eu ions, while that of can be viewed as two units of [EuTi(μ-O)(μ-O)(μ-OCH)(CHOH)] and [EuTi(μ-O)(μ-OH)(μ-OCH)(HO)(CHOH)] connected through four μ-O units from the [EuTi(μ-O)(μ-O)(μ-OCH)(CHOH)] unit to respectively coordinate two Eu and two Ti ions from the [EuTi(μ-O)(μ-OH)(μ-OCH)(HO)(CHOH)] unit. Measurement of their luminescence properties shows that the luminescence lifetime and quantum yield are 1212 μs and 69.6% for and 857 μs and 56.2% for . When F was introduced into in a molar ratio of F to of 1:3, its quantum yield was increased 1.3 times, and the lifetime increased from 1.2 to 1.4 ms. However, no obvious enhancement in the emission intensity was observed in ; even the molar ratio of F to is in the range from 2 to 1/4. Investigation on the structures of and reveals that the luminescence lifetime and quantum yield in is significantly larger than that in are attributed to the vibration of the nonradiative O-H vibration groups in being significantly smaller than that in .
通过4-叔丁基苯甲酸酯配体、Eu(Ac)₃·3H₂O和Ti(OPr)₄在甲醇中的溶剂热反应，合成了两种镧系-钛氧簇（LTOCs），其化学式分别为[EuTi(μ-O)(μ-OH)(CHO)(Ac)(CHOH)(tbba)]·CH₃OH (1) 和[EuTi(μ-O)(μ-OH)(μ-OCH₃)(μ-OCH₃)(H₂O)(CHOH)(tbba)]·Htbba·10H₂O (2)。单晶结构分析表明，1结晶于正交空间群Pnma ，2结晶于三斜空间群P-1。结构上，1的核心可视为通过每个μ-O和μ-OH桥连一个Ti和两个Eu离子形成的[EuTi(μ-O)(μ-OH)]共面单元，而2的核心可视为通过[EuTi(μ-O)(μ-O)(μ-OCH₃)(CHOH)]单元的四个μ-O单元连接的两个单元[EuTi(μ-O)(μ-O)(μ-OCH₃)(CHOH)]和[EuTi(μ-O)(μ-OH)(μ-OCH₃)(H₂O)(CHOH)]，分别配位来自[EuTi(μ-O)(μ-OH)(μ-OCH₃)(H₂O)(CHOH)]单元的两个Eu和两个Ti离子。对其发光性质的测量表明，1的发光寿命和量子产率分别为1212 μs和69.6%，2的发光寿命和量子产率分别为857 μs和56.2%。当以F与1的摩尔比为1:3将F引入1时，其量子产率提高了1.3倍，寿命从1.2 ms增加到1.4 ms。然而，在2中未观察到发射强度的明显增强；即使F与2的摩尔比在2到1/4的范围内。对1和2结构的研究表明，1中的发光寿命和量子产率明显大于2中的，这归因于1中非辐射O-H振动基团的振动明显小于2中的。
