Search

The incorporation of unsaturated [Mn(1,2-dap)] 2+ , [Mn(1,2-dap) 2 ] 2+ , [Mn(2,2-bipy)] 2+ (1,2-dap=1,2-diaminopropane) complex cations with thioarsenate anions of [As III S 3 ] 3− and [As V S 4 ] 3 − led to three new hybrid manganese thioarsenates, namely, [Mn(1,2-dap)] 2 MnAs 2 S 6 ( 1 ), [Mn(1,2-dap) 2 ]{[Mn(1,2-dap)] 2 As 2 S 8 } ( 2 ) and (NH 4 )[Mn(2,2-bipy) 2 ]AsS 4 ( 3 ). In compound 1 , the unsaturated [Mn(1,2-dap)] 2+ complexes, [MnS 4 ] 6− tetrahedra and [As III S 3 ] 3− trigonal-pyramids are condensed to form the 1D [Mn(1,2-dap)] 2 MnAs 2 S 6 chain, whereas compound 2 features 2D layer composed of [Mn(1,2-dap)] 2+ and [Mn(1,2-dap) 2 ] 2+ complexes as well as [As V S 4 ] 3− tetrahedral units. For compound 3 , two [As V S 4 ] 3− anions bridge two [Mn(2,2-bipy)] 2+ complex cations into a butterfly like {[Mn(2,2-bipy)] 2 As 2 S 8 } 2 − anionic unit. Magnetic measurements indicate the ferrimagnetic behavior for compound 1 and antiferromagnetic (AF) behaviors for compounds 2–3 . The UV–vis diffuse-reflectance measurements and electronic structural calculations based on density functional theory (DFT) revealed the title compounds belong to semiconductors with band gaps of 2.63, 2.21, and 1.97 eV, respectively. The narrow band-gap of compound 3 led to the efficient and stable photocatalytic degradation activity over organic pollutant than N-doped P25 under visible light irradiation. [ABSTRACT FROM AUTHOR]

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: Two new ternary ytterbium transition metal stannides, namely, Yb3CoSn6 and Yb4Mn2Sn5, have been obtained by solid-state reactions of the corresponding pure elements in welded tantalum tubes at high temperature. Their crystal structures have been established by single-crystal X-ray diffraction studies. Yb3CoSn6 crystallizes in the orthorhombic space group Cmcm (no. 63) with cell parameters of a=4.662(2), b=15.964(6), c=13.140(5)Å, V=978.0(6)Å3, and Z=4. Its structure features a three-dimensional (3D) open-framework composed of unusual [CoSn3] layers interconnected by zigzag Sn chains, forming large tunnels along the c-axis which are occupied by the ytterbium cations. Yb4Mn2Sn5 is monoclinic space group C2/m (no. 12) with cell parameters of a=16.937(2), b=4.5949(3), c=7.6489(7)Å, β=106.176(4)°, V=571.70(8)Å3, and Z=2. It belongs to the Mg5Si6 structure type and its anionic substructure is composed of parallel [Mn2Sn2] ladders interconnected by unusual zigzag [Sn3] chains, forming large tunnels along the c-axis, which are filled by the ytterbium cations. Band structure calculations based on density function theory methods were also made for both compounds. [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]

Abstract: A new rare earth nickel stannide, Sm2NiSn4, has been prepared by reacting the pure elements at high temperature in welded tantalum tubes. Its crystal structure was established by single crystal X-ray diffraction studies. Sm2NiSn4 crystallizes in the orthorhombic space group Pnma (No. 62) with cell parameters of a=16.878(2)Å, b=4.4490(7)Å, c=8.915(1)Å, and Z=4. Its structure can be viewed as the intermediate type between ZrSi2 and CeNiSi2. Sm2NiSn4 features two-dimensional (2D) corrugated [NiSn4]6− layers in which the 1D Sn zigzag chains and the 2D Sn square sheets are bridged by Ni atoms. The Sm3+ cations are located at the interlayer space. Results of both resistivity measurements and extended-Hückel tight-binding band structure calculations indicate that Sm2NiSn4 is metallic. [Copyright &y& Elsevier]

Low-dimensional hybrid antimony halide perovskites have fascinated the extensive research for their excellent photoluminescence behaviors. However, reasonable optimization of luminescence performance through molecule-level structural regulation remains a formidable challenge. The solution evaporation method with the reaction of organic amines and acid solutions of metal salts is a well-established method for the synthetic of low-dimensional hybrid antimony halide. In this work, by selecting organic cations with different sizes as template molecules, we have successfully synthesized three hybrid antimony halides of 0D [HDBA] 2 SbCl 5 (1), 0D [H 2 ATMP] 2 SbCl 7 (2) and 1D [H 3 PMDETA]Sb 2 Cl 9 (3) (DBA ​= ​dibutylamine, ATMP ​= ​4-amino-2,2,6,6-tetramethylpiperidine, PMDETA = N,N,N′,N″,N″-pentamethyldiethylenetriamine). by the solution evaporation method at room temperature for 2–5 days. These hybrid antimony halides exhibit broadband yellow-light with the highest photoluminescence quantum yield (PLQY) of 8.38%. According to detailed spectroscopy characterizations and theoretical calculations, the broadband light emissions should originate from self-trapped excitons (STEs). These antimony halides could be fabricated as white LEDs with highest color rendering index (>90%). The intrinsic broad-band light emissions and facile assembly process enable these hybrid antimony halides as promising candidates for yellow-light emitting materials. Structural design of hybrid antimony halide : Three antimony chlorides with different structures were prepared by facile solution method. These antimony chlorides have 0D pyramidal [SbCl 5 ]2- and 1D [Sb 2 Cl 9 ]3- chains, and display the broadband yellow-light emissions. [Display omitted] • Lead-free hybrid antimony halides with 0D pyramidal [SbCl 5 ]2- and 1D [Sb 2 Cl 9 ]3- chains. • Broadband yellow-light emissions originate from self-trapped excitons. • These hybrid antimony halides can be fabricated as white LEDs with high CRI. [ABSTRACT FROM AUTHOR]

One new manganese thiogermanate, [(dien)2Mn]Ge2S4 (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P212121 (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å3 and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge2S4]2− anionic chain and a [(dien)2Mn]2+ complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1D [Ge2S4]2− chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV–vis spectra. [ABSTRACT FROM AUTHOR]