Synthesis, Structural Evolution, and Electrical Properties of the Novel Mo12 Cluster Compounds K1+xMo12S14 (x = 0, 1.1,
详细信息 查看全文
- 作者：Soazig Picard ; Patrick Gougeon ; and Michel Potel
- 刊名：Inorganic Chemistry
- 出版年：2006
- 出版时间：February 20, 2006
- 年：2006
- 卷：45
- 期：4
- 页码：1611 - 1616
- 全文大小：269K
- 年卷期：v.45,no.4(February 20, 2006)
- ISSN：1520-510X
文摘
The new structural type (1) K2.3Mo12S14 was prepared by solid-state reaction at 1500 
C in a sealed molybdenumcrucible. The compound crystallizes in the trigonal space group P
1c, Z = 2, (1) a = 9.1720(7) Å, c = 16.403(4)Å. Its crystal structure was determined from single-crystal X-ray diffraction data and consists of interconnectedMo12S14 units that form an original and unprecedented three-dimensional framework in which large tunnels areoccupied randomly by a part of the K+ ions. The remaining K+ ions are localized between two consecutive Mo12S14units along the c axis. By carrying out topotactic oxydo-reduction reactions at low temperature (<100 C), we wereable to remove or insert K+ ions in the channels and thus form isostructural phases K1+xMo12S14 (0 
x 1.6).Thus, we have solved the crystal structures for the following three compositions: (2) K2.1Mo12S14, (3) KMo12S14, and(4) K2.6Mo12S14 ((2) a = 9.1476(4) Å, c = 16.421(1) Å; (3) a = 9.0797(9) Å, c = 16.412(6) Å; and (4) a =9.1990(4) Å, c = 16.426(4) Å). Electrical resistivity measurements carried out on single crystals of K2.3Mo12S14 andKMo12S14 indicate that the former is semiconducting, whereas the latter is metallic. The evolution of the Mo-Modistances with respect to the stoichiometry in potassium is discussed.
C in a sealed molybdenumcrucible. The compound crystallizes in the trigonal space group P1c, Z = 2, (1) a = 9.1720(7) Å, c = 16.403(4)Å. Its crystal structure was determined from single-crystal X-ray diffraction data and consists of interconnectedMo12S14 units that form an original and unprecedented three-dimensional framework in which large tunnels areoccupied randomly by a part of the K+ ions. The remaining K+ ions are localized between two consecutive Mo12S14units along the c axis. By carrying out topotactic oxydo-reduction reactions at low temperature (<100 C), we wereable to remove or insert K+ ions in the channels and thus form isostructural phases K1+xMo12S14 (0 x 1.6).Thus, we have solved the crystal structures for the following three compositions: (2) K2.1Mo12S14, (3) KMo12S14, and(4) K2.6Mo12S14 ((2) a = 9.1476(4) Å, c = 16.421(1) Å; (3) a = 9.0797(9) Å, c = 16.412(6) Å; and (4) a =9.1990(4) Å, c = 16.426(4) Å). Electrical resistivity measurements carried out on single crystals of K2.3Mo12S14 andKMo12S14 indicate that the former is semiconducting, whereas the latter is metallic. The evolution of the Mo-Modistances with respect to the stoichiometry in potassium is discussed.