Li Hailou, Liu Yajie, Zheng Rui, Ma Xing, Chen Lijuan, Zhao Junwei
Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China.
Henan Key Laboratory of Polyoxometalate Chemistry, Institute of Molecular and Crystal Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2017 Apr 5;176:114-122. doi: 10.1016/j.saa.2017.01.016. Epub 2017 Jan 9.
Three rare-earth containing docosatungstates NaH[RE(HO)][RE(HO)][WOH]·36HO [RE=Dy (1), Ho (2), Y (3)] have been synthesized by reaction of NaWO·2HO, dimethylamine hydrochloride (DMAHC) and RE(NO)·6HO in the aqueous solution and characterized by elemental analyses, IR spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. 1-3 are isomorphous and each molecular unit consists of a S-shaped docosatungstate [WOH] polyoxoanion with two supporting [RE(HO)] cations and one disordered [RE(HO)] cation. The [WOH] polyoxoanion can be viewed as combination of two hendecatungstate [WOH] subunits in the staggered fashion by sharing two μ-O atoms. The TG curves of 1-3 reveal the one-step weight loss between 25°C to 700°C. Moreover, both 1 and 2 demonstrate the characteristic luminescence emission behaviors of the corresponding RE ions and their lifetime decay curves can be well fitted to the double exponential function. In addition, the CIE chromaticity coordinates of 1 and 2 have been obtained based on their corresponding emission spectra, and their dominant wavelengths and color purities have been also calculated.
通过在水溶液中使NaWO·2HO、二甲胺盐酸盐（DMAHC）和RE(NO)·6HO反应，合成了三种含稀土的二十二钨酸盐NaH[RE(HO)][RE(HO)][WOH]·36HO [RE = 镝（1）、钬（2）、钇（3）]，并通过元素分析、红外光谱、热重（TG）分析、粉末X射线衍射（PXRD）和单晶X射线衍射对其进行了表征。1 - 3是同构的，每个分子单元由一个S形的二十二钨酸盐[WOH]聚氧阴离子和两个支撑的[RE(HO)]阳离子以及一个无序的[RE(HO)]阳离子组成。[WOH]聚氧阴离子可以看作是两个十一钨酸盐[WOH]亚基通过共享两个μ - O原子以交错方式组合而成。1 - 3的TG曲线显示在25°C至700°C之间有一步失重。此外，1和2都展示了相应稀土离子的特征发光发射行为，并且它们的寿命衰减曲线可以很好地拟合为双指数函数。另外，基于1和2的相应发射光谱获得了它们的CIE色度坐标，并且还计算了它们的主波长和色纯度。
