AVNb3Cl11 (A = K, Rb, Cs, Tl): A Series of Layered Vanadium Niobium Halides Based on Triangular Nb3 Clusters
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- 作者：Thirumalai Duraisamy and Abdessadek Lachgar
- 刊名：Inorganic Chemistry
- 出版年：2003
- 出版时间：December 1, 2003
- 年：2003
- 卷：42
- 期：24
- 页码：7747 - 7751
- 全文大小：227K
- 年卷期：v.42,no.24(December 1, 2003)
- ISSN：1520-510X
文摘
The first quaternary vanadium niobium compounds containing triangular Nb3 clusters corresponding to the generalformula, AVNb3Cl11 (A = K, Rb, Cs, Tl), have been prepared in sealed quartz tubes from stoichiometric amountsof ACl (A = K, Rb, Cs), or Tl metal, VCl3, Nb powder, and NbCl5 heated at 740 
C. The compounds crystallizein the orthorhombic space group Pnma (No. 62). The crystal structures of the Rb and Tl members were determinedby single-crystal X-ray diffraction techniques. Crystal data: a = 12.771(3) Å, b = 6.811(2) Å, c = 17.183(3) Å,V = 1494.6(1) Å3, and Z = 4 for A = Rb; and a = 12.698(5) Å, b = 6.798(3) Å, c = 17.145(10) Å, V =1480.0(13) Å3, and Z = 4 for A = Tl. The crystal structure of AVNb3Cl11 consists of triangular Nb3Cl13 clusters(Nb-Nb = 2.826 Å) connected to each other via four outer ligands to form infinite chains along the b-axis. Thechains are connected by vanadium atoms located in an octahedral environment to form puckered sheets. The A+counterions are located between adjacent sheets and coordinate to twelve chlorine ligands in anticubeoctahedralgeometry. Electronic structure calculations show bonding orbitals similar to those in Nb3Cl8. Magnetic susceptibilitymeasurements show paramagnetic Curie Weiss behavior.
C. The compounds crystallizein the orthorhombic space group Pnma (No. 62). The crystal structures of the Rb and Tl members were determinedby single-crystal X-ray diffraction techniques. Crystal data: a = 12.771(3) Å, b = 6.811(2) Å, c = 17.183(3) Å,V = 1494.6(1) Å3, and Z = 4 for A = Rb; and a = 12.698(5) Å, b = 6.798(3) Å, c = 17.145(10) Å, V =1480.0(13) Å3, and Z = 4 for A = Tl. The crystal structure of AVNb3Cl11 consists of triangular Nb3Cl13 clusters(Nb-Nb = 2.826 Å) connected to each other via four outer ligands to form infinite chains along the b-axis. Thechains are connected by vanadium atoms located in an octahedral environment to form puckered sheets. The A+counterions are located between adjacent sheets and coordinate to twelve chlorine ligands in anticubeoctahedralgeometry. Electronic structure calculations show bonding orbitals similar to those in Nb3Cl8. Magnetic susceptibilitymeasurements show paramagnetic Curie Weiss behavior.