Double Sandwich Polyoxometalate and Its Fe(III) Substituted Derivative, [As2Fe5Mo21O82]17鈥?/sup> and [As2Fe6Mo20O
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- 作者：Xiangqian Dong ; Yanping Zhang ; Bin Liu ; Yanzhong Zhen ; Huaiming Hu ; Ganglin Xue
- 刊名：Inorganic Chemistry
- 出版年：2012
- 出版时间：February 20, 2012
- 年：2012
- 卷：51
- 期：4
- 页码：2318-2324
- 全文大小：386K
- 年卷期：v.51,no.4(February 20, 2012)
- ISSN：1520-510X
文摘
A double sandwich polyoxometalate and its Fe(III) substituted derivative, [As2Fe5Mo21O82]17鈥?/sup> (1) and [As2Fe6Mo20O80(H2O)2]16鈥?/sup> (2), were synthesized and characterized by single-crystal X-ray diffraction, infrared spectroscopy, fluorescent spectroscopy, UV spectra, thermogravimetry-differential scanning calorimetry analyses, electrospray ionization mass spectrometry, and magnetism measurements. The polyoxoanion is composed of a central fragment FeMo7O28 for 1 (Fe2Mo6O26(H2O)2 for 2) and two external AsMo7O27 fragments linked together by two distinct edge-sharing dimeric clusters Fe2O10 to lead to a C2v molecular symmetry. The central FeMo7O28 fragment and external AsMo7O27 fragment have a similar structure, and both of them can be viewed as a monocapped hexavacant 伪-Keggin subunit with a central FeO4 group or a central AsO3 group. Both of the polyoxoanions contain a oxo-bridged FeIII5 magnetic core with the angles of Fe鈥揙鈥揊e in the range of 96.4(4)鈥?25.7(5)掳, and magnetism measurements show an overall ferromagnetic interactions among the five-nuclearity cluster Fe5 with the spin ground state S = 15/2.