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Abstract: K2Mg5−x Sn3 (x=0.28) and K3Mg18 Tt 11 (Tt=Sn, Pb) have been synthesized by reacting the mixture of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction studies. K2Mg5−x Sn3 (x=0.28) is isostructural with Ni7−x SbQ 2 (Q=Se, Te) series and features 2D corrugated [Mg5−x Sn3] layers that are separated by K+ cations. The structure of K3Mg18 Tt 11 (Tt=Sn, Pb) is closely related to the Ho2Rh12As7 structural type and features 3D [Mg18 Tt 11] framework composed of 1D [Mg18 Tt 11] columns that are interconnected via Mg–Tt bonds, forming 1D hexagonal tunnels occupied by the K+ cations. Electronic structure calculations indicate that Mg atoms can function as either electron donor or as a participator in the network along with Tt atoms. Magnetic property measurements and band structure calculations indicate that these compounds are metallic. [Copyright &y& Elsevier]

Abstract: Four new isostructural rare earth manganese stannides, namely RE 3MnSn5−x (x=0.16(6), 0.29(1) for RE=Tm, x=0.05(8), 0.21(3) for RE=Lu), have been obtained by reacting the mixture of corresponding pure elements at high temperature. Single-crystal X-ray diffraction studies revealed that they crystallized in the orthorhombic space group Pnma (No. 62) with cell parameters of a=18.384(9)–18.495(6)Å, b=6.003(3)–6.062(2)Å, c=14.898(8)–14.976(4)Å, V=1644.3(14)–1679.0(9)Å3 and Z=8. Their structures belong to the Hf3Cr2Si4 type and feature a 3D framework composed of 1D [Mn2Sn7] chains interconnected by [Sn3] double chains via Sn–Sn bonds, forming 1D large channels based on [Mn4Sn16] 20-membered rings along the b-axis, which are occupied by the rare earth atoms. Electronic structure calculations based on density functional theory (DFT) for idealized “RE3MnSn5” model indicate that these compounds are metallic, which are in accordance with the results from temperature-dependent resistivity measurements. [ABSTRACT FROM AUTHOR]

Abstract: The title compounds have been obtained by solid state reactions of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction studies. Yb5Ni4Sn10 adopts the Sc5Co4Si10 structure type and crystallizes in the tetragonal space group P4/mbm (No. 127) with cell parameters of a=13.785(4)Å, c=4.492 (2)Å, V=853.7(5)Å3, and Z=2. Yb7Ni4Sn13 is isostructural with Yb7Co4InGe12 and crystallizes in the tetragonal space group P4/m (No. 83) with cell parameters of a=11.1429(6)Å, c=4.5318(4)Å, V=562.69(7)Å3, and Z=1. Both structures feature three-dimensional (3D) frameworks based on three different types of one-dimensional (1D) channels, which are occupied by the Yb atoms. Electronic structure calculations based on density functional theory (DFT) indicate that both compounds are metallic. These results are in agreement with those from temperature-dependent resistivity and magnetic susceptibility measurements. [Copyright &y& Elsevier]

Abstract: Three new ternary potassium(I) zinc(II) or cadmium(II) tellurides, namely, K2Cd2Te3, K6CdTe4 and K2ZnTe2, were synthesized by solid-state reactions of the mixture of pure elements of K, Cd (or Zn) and Te in Nb tubes at high temperature. K2Cd2Te3 belongs to a new structure type and its structure contains a novel two-dimensional [Cd2Te3]2− layers perpendicular to the b-axis. K(5) cation is located at the center of five member rings of the 2D [Cd2Te3]2− layer, whereas other K+ cations occupy the interlayer space. K6CdTe4 with a K6HgS4 type structure features a “zero-dimensional” structure composed of isolated CdTe4 tetrahedra separated by the K+ ions. K2ZnTe2 in the K2ZnO2 structural type displays 1D [ZnTe2]2− anionic chains of edge sharing [ZnTe4] tetrahedra separated by the potassium(I) ions. K2Cd2Te3, K6CdTe4 and K2ZnTe2 revealed a band gap of 1.93, 2.51 and 3.0eV, respectively. [Copyright &y& Elsevier]