title: Synthesis, structure, spectroscopic and ferroelectric properties of an acentric polyoxotungstate containing 1:2-type [Sm(α-PW₁₁O₃₉)₂]¹¹⁻ fragment and D-proline components.
abstract: An organic-inorganic hybrid mono-Sm(III) substituted phosphotungstate KNa3[HPro]₇[Sm(α-PW₁₁O₃₉)₂]·Pro·₁₈H₂O (1) (Pro=D-proline) has been synthesized in the conventional aqueous solution and structurally characterized by elemental analyses, inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses, IR spectra, UV spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. The molecule of 1 consists of a classical 1:2-type [Sm(α-PW₁₁O₃₉)₂](11-) fragment and free D-proline components. It should be pointed out that the synergistic action between the in-situ formed chiral [Sm(α-PW₁₁O₃₉)₂](11-) fragment and chiral D-proline components results in the formation of the chiral 1. The luminescence emission of 1 reveals three characteristic bands that derive from the (4)G₅/₂→(6)H₅/₂, (4)G₅/₂→(6)H₇/₂ and (4)G₅/₂→(6)H₉/₂ transitions of the Sm(III) cation as well as the synergistic contribution of the O→W transitions of [α-PW₁₁O₃₉](7-) moieties and a π(*)-n or π(*)-π transitions of Pro. Its ferroelectric behavior has been measured.
authors.affiliation: Institute of Molecular and Crystal Engineering, Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China; College of Medicine, Henan University, Kaifeng, Henan 475004, PR China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Molecular and Crystal Engineering, Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China.
authors.forename: Hailou
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Molecular and Crystal Engineering, Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China.
authors.forename: Jingli
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Institute of Molecular and Crystal Engineering, Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China; State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China. Electronic address: zhaojunwei@henu.edu.cn.
authors.forename: Junwei
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Institute of Molecular and Crystal Engineering, Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China. Electronic address: ljchen@henu.edu.cn.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Chen
mesh_terms: D060326:Chemistry Techniques, Synthetic; D018360:Crystallography, X-Ray; D049449:Luminescence; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010772:Phosphotungstic Acid / Q000737:chemistry; D011392:Proline / Q000737:chemistry*; D013054:Spectrophotometry, Atomic; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013818:Thermogravimetry; D014414:Tungsten / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D009942:Organometallic Compounds; D010772:Phosphotungstic Acid; D011392:Proline; D014414:Tungsten
keywords: Ferroelectricity; Luminescence; Polyoxometalate; Polyoxotungstate; Proline