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1.
Quaternary chalcogenides InSn2Bi3Se8 and In0.2Sn6Bi1.8Se9 were synthesized on direct combination of their elements in stoichiometric ratios at T>800 °C under vacuum. Their structures were determined with X-ray diffraction of single crystals. InSn2Bi3Se8 crystallizes in monoclinic space group C2/m (No. 12) with a=13.557(3) Å, b=4.1299(8) Å, c=15.252(3) Å, β=115.73(3)°, V=769.3(3) Å3, Z=2, and R1/wR2/GOF=0.0206/0.0497/1.092; In0.2Sn6Bi1.8Se9 crystallizes in orthorhombic space group Cmc21 (No. 36) with a=4.1810(8) Å, b=13.799(3) Å, c=31.953(6) Å, V=1843.4(6) Å3, Z=4, and R1/wR2/GOF=0.0966/0.2327/1.12. InSn2Bi3Se8 and In0.2Sn6Bi1.8Se9 are isostructural with CuBi5S8 and Bi2Pb6S9 phases, respectively. The structures of InSn2Bi3Se8 and In0.2Sn6Bi1.8Se9 feature a three-dimensional framework containing slabs of NaCl-(311) type with varied thicknesses. Calculations of the electronic structure and measurements of electrical conductivity indicate that these materials are semiconductors with narrow band gaps. Both compounds show n-type semiconducting properties with Seebeck coefficients −270 and −230 μV/K at 300 K for InSn2Bi3Se8 and In0.2Sn6Bi1.8Se9, respectively. 相似文献
2.
Three rare earth compounds, KEu[AsS4] (1), K3Dy[AsS4]2 (2), and Rb4Nd0.67[AsS4]2 (3) have been synthesized employing the molten flux method. The reactions of A2S3 (A = K, Rb), Ln (Ln = Eu, Dy, Nd), As2S3, S were accomplished at 600 °C for 96 h in evacuated fused silica ampoules. Crystal data for these compounds are: 1, monoclinic, space group P21/m (no. 11), a = 6.7276(7) Å, b = 6.7190(5) Å, c = 8.6947(9) Å, β = 107.287(12)°, Z = 2; 2, monoclinic, space group C2/c (no. 15), a = 10.3381(7) Å, b = 18.7439(12) Å, c = 8.8185(6) Å, β = 117.060(7)°, Z = 4; 3, orthorhombic, space group Ibam (no. 72), a = 18.7333(15) Å, b = 9.1461(5) Å, c = 10.2060(6) Å, Z = 4. 1 is a two-dimensional structure with 2∞[Eu(AsS4)]− layers separated by potassium cations. Within each layer, distorted bicapped trigonal [EuS8] prisms are linked through distorted [AsS4]3− tetrahedra. Each Eu2+ cation is coordinated by two [AsS4]3− units by edge-sharing and bonded to further two [AsS4]3− units by corner-sharing. Compound 2 contains a one-dimensional structure with 1∞[Dy(AsS4)2]3− chains separated by potassium cations. Within each chain, distorted bicapped trigonal prisms of [DyS8] are linked by slightly distorted [AsS4]3− tetrahedra. Each Dy3+ ion is surrounded by four [AsS4]3− moieties in an edge-sharing fashion. For compound 3 also a one-dimensional structure with 1∞[Nd0.67(AsS4)2]4− chains is observed. But the Nd position is only partially occupied and overall every third Nd atom is missing along the chain. This cuts the infinite chains into short dimers containing two bridging [As4]3− units and four terminal [AsS4]3− groups. 1 is characterized with UV/vis diffuse reflectance spectroscopy, IR, and Raman spectra. 相似文献
3.
The new compounds K12Ta6Se35 and KTaTe3 have been synthesized through the reaction of Ta metal with a K2Qn(Q = Se, Te) flux. K12Ta6Se35, crystallizes with 4 formula units in space group Pbcn of the orthorhombic system in a cell of dimensions a = 8.3390(17) Å, b = 13.259(3) Å, c = 56.023(11) Å (t = −120 °C). KTaTe3 crystallizes with 20 formula units (or 4 formula units of K5Ta5Te15) in the monoclinic space group P21/c in a cell of dimension a = 7.7177(15) Å, b= 13.826(3) Å, c = 30.981(6) Å, and β = 90.11(3)° (t = −120 °C). Each structure consists of infinite anionic chains of Ta-containing polyhedra well separated by K+ cations. In K12Ta6Se35 there are Ta2Se11 units formed by the face sharing of two TaSe7 elongated bipyramids. These Ta2Se11 units are in turn interconnected by Se2 and Se3 units to form α1[Ta6Se3Se3512−]infinite chains. In KTaTe3, the α1[TaTe3−] infinite chains arise from the face sharing of distorted TaTe6 octahedra. 相似文献
4.
Xuean Chen Fangping Song Xinan Chang Hegui Zang Weiqiang Xiao 《Journal of solid state chemistry》2009,182(11):3091-3097
Two oxoborates, (Pb3O)2(BO3)2MO4 (M=Cr, Mo), have been prepared by solid-state reactions below 700 °C. Single-crystal XRD analyses showed that the Cr compound crystallizes in the orthorhombic group Pnma with a=6.4160(13) Å, b=11.635(2) Å, c=18.164(4) Å, Z=4 and the Mo analog in the group Cmcm with a=18.446(4) Å, b=6.3557(13) Å, c=11.657(2) Å, Z=4. Both compounds are characterized by one-dimensional chains formed by corner-sharing OPb4 tetrahedra. BO3 and CrO4 (MoO4) groups are located around the chains to hold them together via Pb–O bonds. The IR spectra further confirmed the presence of BO3 groups in both structures and UV–vis diffuse reflectance spectra showed band gaps of about 1.8 and 2.9 eV for the Cr and Mo compounds, respectively. Band structure calculations indicated that (Pb3O)2(BO3)2MoO4 is a direct semiconductor with the calculated energy gap of about 2.4 eV. 相似文献
5.
Dy5Ni0.66Bi2.34 and Lu5Ni0.56Sb2.44 were synthesized by arc-melting and were found to adopt an orthorhombic Yb5Sb3-type structure. Cell parameters are a = 12.075(2), b = 9.165(2), c = 8.072(1) Å for Dy5Ni0.66Bi2.34 and a = 11.6187(9), b = 8.933(1) and c = 7.8377(6) Å for Lu5Ni0.56Sb2.44. Dy5Ni0.66Bi2.34 undergoes a step-like ferromagnetic transition around 66 K. Magnetocaloric effect in terms of the magnetic entropy change, ΔS, reaches −3.73 J/kg K at 75 K for Dy5Ni0.66Bi2.34. 相似文献
6.
Clarence Anglin 《Journal of solid state chemistry》2010,183(7):1529-1535
The quaternary manganese tin bismuth selenide, Mn1.34Sn6.66Bi8Se20 was synthesized by combining constituent elements at 723 K. Single crystal structure determination revealed that Mn1.34Sn6.66Bi8Se20 is isostructural to the mineral pavonite, AgBi3S5, crystallizing in the monoclinic space group C2/m (#12) with a=13.648(3) Å; b=4.175(1) Å; c=17.463(4) Å; β=93.42(3)°. In the structure, two kinds of layered modules, denoted A and B, alternate along [0 0 1]. Module A consists of paired chains of face-sharing monocapped trigonal prisms (around Bi/Sn) separated by a single chain of edge-sharing octahedra (around Mn/Sn). Module B represents a NaCl-type fragment of edge-sharing [(Bi/Sn)Se6] octahedra. Mn1.34Sn6.66Bi8Se20 is an n-type narrow gap semiconductor with Eg∼0.29 eV. At 300 K, thermopower, electrical conductivity and lattice thermal conductivity values are −123 μV/K, 47 S/cm and 0.6 W/m K, respectively. Mn1.34Sn6.66Bi8Se20 is paramagnetic at high temperatures and undergoes antiferromagnetic transition at TN=10 K. 相似文献
7.
Artem M. Abakumov Joke Hadermann Alexander A. Tsirlin Haiyan Tan Jo Verbeeck Haitao Zhang Evgeny V. Dikarev Roman V. Shpanchenko Evgeny V. Antipov 《Journal of solid state chemistry》2009,182(8):2231-2238
The crystal structure of the Pb4Mn9O20 compound (previously known as “Pb0.43MnO2.18”) was solved from powder X-ray diffraction, electron diffraction, and high resolution electron microscopy data (S.G. Pnma, a=13.8888(2) Å, b=11.2665(2) Å, c=9.9867(1) Å, RI=0.016, RP=0.047). The structure is based on a 6H (cch)2 close packing of pure oxygen “h”-type (O16) layers alternating with mixed “c”-type (Pb4O12) layers. The Mn atoms occupy octahedral interstices formed by the oxygen atoms of the close-packed layers. The MnO6 octahedra share edges within the layers, whereas the octahedra in neighboring layers are linked through corner sharing. The relationship with the closely related Pb3Mn7O15 structure is discussed. Magnetization measurements reveal a peculiar magnetic behavior with a phase transition at 52 K, a small net magnetization below the transition temperature, and a tendency towards spin freezing. 相似文献
8.
Kateryna V. Terebilenko Igor V. Zatovsky Nikolay S. Slobodyanik Konstantin V. Domasevitch Denis V. Pushkin Vyacheslav N. Baumer Valentina S. Sudavtsova 《Journal of solid state chemistry》2007,180(12):3351-3359
Phase equilibrium in the pseudo-quaternary system K2O–MoO3–P2O5–Bi2O3 was studied as three-component solvent K2MoO4–KPO3–MoO3 containing 15 mol% Bi2O3 during slow cooling and spontaneous crystallization. The results of the investigation were shown on a composition diagram, which indicates the crystallization fields of K2Bi(PO4)(MoO4), K5Bi(MoO4)4, BiPO4 and K3Bi5(PO4)6. New phosphate K3Bi5(PO4)6 was characterized by single-crystal X-ray diffraction (space group C2/c, a=17.680(4), b=6.9370(14), c=18.700(4) Å, β=113.79(3)°) and FTIR spectroscopy. The possibility of lone electron pair stereoactivity of bismuth was suggested using the calculations of characteristics of the Voronoi–Dirichlet polyhedra for K3Bi5(PO4)6 and K2Bi(PO4)(MoO4). 相似文献
9.
Abdeljalil Assoud 《Journal of solid state chemistry》2004,177(7):2249-2254
Ba4LaGe3SbSe13 was prepared by reacting the elements under exclusion of air at 700°C, followed by slow cooling to room temperature. It crystallizes in a new type of the monoclinic space group P21/c, with lattice dimensions of a=1633.30(9) pm, b=1251.15(7) pm, c=1303.21(7) pm, β=103.457(2)°, V=2590.0(2) 106 pm3 (Z=4). The structure contains isolated GeSe4 as well as Ge2Se7 digermanate units. Two of the latter are interconnected via an Sb2Se4 bridge yielding an almost linear complex anion [Ge2Se7-Sb2Se4-Ge2Se7]14−. The oxidation states are assigned to be BaII, LaIII, GeIV, SbIII, and Se−II, in accord with an electronically saturated nonmetal. The lone pair of SbIII reflects itself in highly irregular Se coordination. The red color of the material is indicative of semiconducting behavior with an activation energy of 2.0 eV. Electronic structure calculations based on the LMTO approximation point to a smaller gap, typical for this calculation method. We utilized the COHP tool to explore the bonding character of the different Sb-Se interactions. 相似文献
10.
Kuei-Bo Chen 《Journal of solid state chemistry》2010,183(11):2616-2622
Quaternary chalcogenides PbxSn6−xBi2Se9 (x=0-4.36) were synthesized with solid-state methods; their structures were determined from the X-ray diffraction of single crystals. PbxSn6−xBi2Se9 crystallizes in an orthorhombic space group Cmcm (No. 63); the structure features a three-dimensional framework containing slabs of NaCl-(3 1 1) type that exhibits identical layers containing seven octahedra units, which expand along the direction [0 1 0]. Each slab contains fused rectangular units that are connected to each other with M-Se contacts in a distorted octahedral environment. Calculations of the band structure, measurements of Seebeck coefficient and electrical conductivity confirm that these compounds are n-type semiconductors with small band gaps and large electrical conductivities. 相似文献
11.
Paul M. Forster Andrea R. Burbank Melanie C. O'Sullivan Nathalie Guillou Carine Livage Grard Frey Norbert Stock Anthony K. Cheetham 《Solid State Sciences》2005,7(12):1549
A new form of cobalt succinate has been discovered using high-throughput methods and its structure was solved by single crystal X-ray diffraction. Co7(C4H4O4)4(OH)6(H2O)37H2O crystallizes in the monoclinic space group P21/c with cell parameters: a=7.888(2) Å, b=19.082(6) Å, c=23.630(7) Å, β=91.700(5)°, V=3555(2) Å3, R1=0.0469. This complex structure, containing 55 crystallographically distinct non-hydrogen atoms, is compared to the previously reported nickel phase, characterized using ab initio structure solution from synchrotron powder diffraction data. 相似文献
12.
A new layered tin(II) phosphate [Sn2(PO4)2]2−[C2N2H10]2+·H2O was synthesized by hydrothermal technique. It crystallizes in monoclinic space groupP21/c(No. 14) with lattice parametersa=9.4112(1) Å;b=8.5998(1) Å;c=15.9921(2) Å;β=100.009(1)°;V=1274.61(2);Z=4;R=2.06%;Rw=2.17%. The structure consists of inorganic layers, comprising a network of strictly alternating SnO3and PO4moieties and held together by strong hydrogen bonding between the layers. Protonated ethylenediamine and water molecules are trapped between the layers. 相似文献
13.
Yahong Xie Shu Yin Hisanori Yamane Takatoshi Hashimoto Tsugio Sato 《Solid State Sciences》2009,11(9):1703-1708
Nanopowder of a new tin(II) titanium(IV) oxide hydroxide fluoride, Sn1.24Ti1.94O3.66(OH)1.50F1.42 with the pyrochlore-type structure (cubic a = 10.3777(7) Å, space group Fd-3m) was prepared by using a microwave-assisted solvothermal reaction. The grain size of the nanopowder was 20–30 nm in diameter. Sn1.24Ti1.94O3.66(OH)1.50F1.42 decomposed above 300 °C, but could be sintered to relative density greater than 99% by a hydrothermal hot-pressing (HHP) method at 270 °C and 80 MPa for 4 h. The synthesized powder and solidified body obtained using HHP showed significantly different color, probably due to the difference in water content. 相似文献
14.
Zhi-En Lin Jie Zhang Shou-Tian Zheng Qiao-Hua Wei Guo-Yu Yang 《Solid State Sciences》2003,5(11-12):1435-1438
The hydrothermal synthesis, crystal structure and some properties of a zinc phosphite with a neutral cluster, [Zn(2,2′-bipy)]2(H2PO3)4, are reported. This compound crystallizes in the triclinic system of space group P-1 (No. 2), a=8.3067(5) Å, b=8.9545(4) Å, c=10.0893(6) Å, α=95.448(2)°, β=99.7530(10)°, γ=103.461(2)°, V=712.23(7) Å3, Z=1. The cluster consists of 4-membered rings formed by alternating ZnO3N2 square pyramids and H2PO3 pseudo pyramids, with two “hanging” H2PO3 groups attached to each of the Zn centers. The clusters are linked together by extensive multipoint hydrogen bonding involving the phosphite units to form a sheet-like structure. This compound represents the first example of zinc phosphite with P---OH bonds. An intense photoluminescence was observed from this compound upon photoexcitation at 388 nm. 相似文献
15.
A tin(II) squarate Sn2O(C4O4)(H2O) was synthesized by hydrothermal technique. It crystallizes in the monoclinic system, space group C2/m (no. 12) with lattice parameters a=12.7380(9) Å, b=7.9000(3) Å, c=8.3490(5) Å, β=121.975(3)°, V=712.69(7) Å3, Z=4. The crystal structure determined with an R=0.042 factor, consists of [(Sn4O10)(H2O)2] units connected from one another in the [101] and [010] directions via squarate groups to form layers separated by Sn(II) lone pairs. This compound presents the same remarkable structural arrangement as observed in the tin-oxo-fluoride Sn2[Sn2O2F4] inorganic compound with Sn(II) lone pairs E(1) and E(2) concentrated in large rectangular-shape tunnels running along [001] direction. 相似文献
16.
Nicole Pienack Karina Mller Christian Nther Wolfgang Bensch 《Solid State Sciences》2007,9(12):1110-1114
The new thiostannate (1,4-dabH)2MnSnS4 (1,4-dab = 1,4-diaminobutane) was synthesized under solvothermal conditions. The compound crystallizes in the non-centrosymmetric space group Fdd2 with a = 22.8124(15) Å, b = 24.7887(16) Å, c = 6.4153(6) Å, Z = 8, and V = 3627.8(5) Å3. The structure consists of one-dimensional straight anionic chains composed of alternating SnS4 and MnS4 tetrahedra sharing common edges. The chains are directed along [001] and are surrounded by the organic cations which form undulated chains along [100] by strong intermolecular N–HN hydrogen bonding interactions. Several SH contacts suggest weak interactions between the anionic chains and the cations. The band gap amounts to 2.9 eV indicating that the compound is a photo-conductor. The compound is stable up to about 190 °C and decomposes in two distinct steps above this temperature. 相似文献
17.
The hydrothermal synthesis, single crystal structure, and some physical properties of Ba2(VO2)(PO4)(HPO4)·H2O, a new barium vanadium(V) phosphate hydrate, are reported. This phase is built up from one-dimensional chains of unusual VO5trigonal bipyramids and (H)PO4tetrahedra, fused together via V–O–P linkages. These anionic chains propagate along the polar [010] direction. 11-Coordinate barium cations and water molecules occupy the interchain regions and link the chains together. Structural data for this phase and other known barium vanadium phosphates are briefly compared. Crystal data: Ba2(VO2)(PO4)(HPO4)·H2O,Mr=566.57, monoclinic, space groupP21(No. 4),a=5.0772(5) Å,b=8.724(2) Å,c=10.806(1) Å,β=90.795(8)°,V=478.6(1) Å3,Z=2,R=2.65%,Rw=2.89% [147 parameters, 1893 observed reflections withI>3σ(I)]. 相似文献
18.
Yuandong Wu 《Journal of solid state chemistry》2007,180(1):113-118
The quaternary compound Rb2BaNb2Se11 has been synthesized by reacting Nb metal with an in situ formed flux of Rb2Se3, BaSe and Se at 773 K. Rb2BaNb2Se11 crystallizes in the monoclinic space group P21/c with four formula units and lattice parameters a=7.8438(5) Å, b=13.6959(6) Å, c=17.0677(13) Å, β=97.917(9)°. The structure consists of one-dimensional anionic chains formed by interconnection of dimeric [Nb2Se11] units. The chains are directed along the crystallographic c-axis with Rb+ and Ba2+ ions being located between the chains. The [Nb2Se11] units are formed by face sharing of two NbSe7 bipyramids and are joined by Se22− dianions to form infinite 1∞[Nb2Se114−] chains. The compound was characterized with infrared spectroscopy in the FIR region, Raman and UV/Vis diffuse reflectance spectroscopy. 相似文献
19.
The ternary Zintl compound europium tin antimonide, EuSn3Sb4, has been synthesized at 900°C in the presence of a tin flux, and its structure has been determined by single-crystal X-ray diffraction methods. It crystallizes in the orthorhombic space group D162h-Pnma with a=9.954(2), b=4.3516(7), c=22.650(4) Å, and Z=4 at 22°C. EuSn3Sb4 is isostructural to SrSn3Sb4; it possesses channels defined by an anionic framework of shared SnSb4 tetrahedra, SnSb3 trigonal pyramids, and Sb–Sb zigzag chains, and it is filled by Eu2+ cations. Resistivity measurements indicate weakly metallic behavior for ASn3Sb4 (A=Eu, Sr) and the structurally related Ba2Sn3Sb6. The anisotropic metallic nature of these compounds is explained through extended Hückel band structure calculations. 相似文献
20.
Wilfried Hermes Stefan Linsinger Ratikanta Mishra Rainer P?ttgen 《Monatshefte für Chemie / Chemical Monthly》2008,30(8):1143-1149
The intermetallic cerium compounds Ce3-Pd3Bi4, CePdBi, and CePd2Zn3 were synthesized from the elements in sealed tantalum ampoules in an induction furnace. The compounds were characterized
by X-ray powder and single crystal diffraction: CeCo3B2 type (ordered version of CaCu5), P6/mmm, a = 538.4(4), c = 427.7(4) pm, wR2 = 0.0540, 115 F
2 values, 9 variables for CePd2Zn3 and Y3Au3Sb4 type, I
[`4]{\bar 4}
3d, a = 1005.2(2) pm, w
R2 = 0.0402, 264 F
2 values, 9 variables for Ce3Pd3Bi4, and MgAgAs type, a = 681.8(1) pm for CePdBi. The bismuthide structures are build up from three-dimensional networks of corner-sharing PdBi4 tetrahedra with Pd–Bi distances of 281 (Ce3Pd3Bi4) and 296 pm (CePdBi), respectively. The cerium atoms are located in larger voids of coordination number 12 (Ce3Pd3Bi4) and 10 (CePdBi). In CePd2Zn3 the cerium atoms fill larger channels within the three-dimensional [Pd2Zn3] network with 18 (6 Pd + 12 Zn) nearest neighbors. The three compounds contain stable trivalent cerium with experimental
magnetic moments of μeff = 2.70(2), 2.48(1), and 2.49(1) μB/Ce atom for CePd2Zn3, Ce3Pd3Bi4, and CePdBi, respectively. Susceptibility and specific heat data gave no hint for magnetic ordering down to 2.1 K. 相似文献