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1.
On the Crystal Structure of Ba3In2Zn5O11. An Oxoindate/zincatesol;zincate with Zn10O20 and In4O16 Macropolyhedra with Zn2+ in Tetrahedral Coordination by O2? Ba3In2Zn5O11 was prepared for the first time by a flux technique and investigated by single crystal X-ray work. It crystallizes with cubic symmetry, space group T-F4 3m, a = 13.3588 Å, Z = 8. Zn2+ show tetrahedral coordination by O2?, forming Zn10O20 macropolyhedra. In addition the nZn/Osol;O part of the crystal structure is made up of Zn10O20 parts. Edge connection of four InO6 octahedra results in In4O16 groups. The crystal structure will be shown and discussed.  相似文献   

2.
On the Synthesis and Crystal Structure of Ba6Lu4Zn10O22 with [OBa6] Octahedra Single crystals of Ba6Lu4Zn10O22 have been prepared by high temperature reactions and investigated by X-ray techniques. This compound is isotypic to Ba3In2Zn5O11 and the first member of the Rare Earth elements. Ba6Lu4Zn10O22 crystallizes with cubic symmetry, space group T-F4 3m, a = 13.452(1) Å and Z = 4. Zn2+ shows a tetrahedral, Lu3+ an octahedral and Ba2+ a three-fold capped trigonal prismatic coordination by O2?. The ZnO4 tetrahedra and LuO6 octahedra are forming macro polyhedra of the type Zn10O20 and Lu4O16. A discussion is given for the Ba6O33 and Ba6O42 groups.  相似文献   

3.
About the Crystal Structure of Ba3In2O6 Single crystals of Ba3In2O6 could be prepared by recrystallization of a flux and by solid state reaction in closed platinium tubes, respectively. Ba3In2O6 crystallizes with tetragonal symmetry (space group 14/mmm, a = 4.1868; c = 21.7041 Å, Z = 2). Single crystal X-ray work lead to a crystal structure like La2-xSr1+xCu2O6-δ therefor Ba3In2O6 is a modified member of the Sr3Ti2O7-Type. The coordinations of Ba2+ and In3+ are described and the relations to the Sr3Ti2O7-type are discussed.  相似文献   

4.
On the Atomic Distribution in Ba2SrIn2O6 with a Contribution to the Existence of the Calciumferrite-Type of Oxoindates (I) Ba2SrIn2O6 and (II) Sr0.93Ba0.07In2O4 were prepared and investigated by single crystal X-ray technique. I crystallizes with tetragonal symmetry, space group D – I4/mmm, a = 4.168; c = 21.290 Å; Z = 2; II belongs to the orthorhombic space group D – Pnma, a = 9.858; b = 3.273; c = 11.520 Å; Z = 4. I shows in respect to the formerly investigated compound BaSr2In2O6 an unexpected statistically distribution of Ba2+ and Sr2+ with the La2SrCu2O6 type. II marks the range of existence of the calciumferrite type within the alkaline earth oxoindates in direction of large radii of M2+ ions.  相似文献   

5.
On the Crystal Structure of In3Mo11O17 and the Physical Properties of Oligomeric Oxomolybdates In3Mo11O17 is characterized by its molybdate framework Mo22O348? belonging to the general series Mo4n+2O6n+4x? (with n = 5). The phase grows in star-like aggregates and crystallizes within the orthorhombic system (a = 988.0(2) pm, b = 951.2(2) pm, c = 3 176.7(4) pm). There are oligomeric clusters built from five trans edge-sharing Mo6 octahedra, surrounded by O atoms over all empty edges according to the Aufbau principle Mo22OOO. In the remaining structural channel one finds an In68+ polycation which is geometrically equivalent with the one of In11Mo40O62. The Mo—O and Mo—Mo distances within the cluster are the same like in In11Mo40O62, too, but there are shorter inter cluster distances (306 pm) in In3Mo11O17. Disorder in the structure may be understood in terms of the presence of constitutional isomers. While the electrical resistivity of PbMo5O8 resembles the one of a strongly disturbed metal (with a local minimum around 120 K), the temperature characteristic of Tl0.8Sn0.6Mo7O11 is typical for a semiconductor. Oxomolybdates with even longer oligomers like In11Mo40O62 and In3Mo11O17 show metallic conductivity. This course corresponds with the sizes of the clusters and their electronic intercoupling which can be estimated from the specific lengths of the inter cluster distances. The effective magnetic moment grows with increasing cluster length from 0.97 μB (PbMo5O8) to 1.40 μB (In11Mo40O62) per cluster (exception: In3Mo11O12), and so does the contribution of the temperature-independent paramagnetism (from 890 to 2191 × 10?6$ \frac{{{\rm emu}}}{{{\rm mol}}} $ per cluster). Thus, a single condensed octahedron carries roughly 440 × 10?6$ \frac{{{\rm emu}}}{{{\rm mol}}} $ as a temperature-independent paramagnetism, similar to the M6X17 halide clusters. In11Mo40O62 shows an interesting change in the temperature dependence of its magnetic suszeptibility.  相似文献   

6.
《Solid State Sciences》2001,3(1-2):143-153
The hydrothermal synthesis, single crystal structure analysis, spectroscopic and thermal stability studies of the compounds Ba3(In1−xMx)2(HXO4)6 (0≤x≤1; M=Cr, Fe; X=P, As) are reported. The 3D framework of these new phosphates can be described as a pillared layered framework. The metal cations (In3+, Fe3+, and Cr3+) occupy two crystallographically independent octahedral sites, M(1) and M(2). The layers are formed of M(2)O6 octahedra and (HPO4) tetrahedra sharing corners, with M(1)O6 octahedra serving as pillars between adjacent layers. Single crystal study of Ba3(In0.5Fe0.5)(HPO4)6 shows that indium and iron segregate between the two metal sites with Fe occupying primarily the site M(1) and In located primarily in M(2) site. Interactions between the building units within the layers occur through hydrogen bonding. Barium cations are located between the pillars, in 8-membered ring tunnels and are coordinated by 12 oxides. The phases loose three water molecules through condensation of six HXO4 groups to form Ba2M2(X2O7)3 at temperatures between 480 and 600 °C. Mössbauer spectroscopy shows the presence of high-spin Fe3+ in octahedral coordination.  相似文献   

7.
Single crystals of the quaternary compound Ba8Cu3In4N5 were prepared by heating Ba, Cu, and In in a Na flux at 1023 K under 7 MPa of N2, and by slow cooling from this temperature. The crystal structure was analyzed by single-crystal X-ray diffraction. It crystallizes in an orthorhombic cell (space group Immm (No. 71), Z=2) with a=4.0781(6), b=12.588(2), and c=19.804(3) Å at 298 K. The structural formula is expressed as Ba8[CuN2]2 [CuN]In4. Nitridocuprates of one-dimensional chains 1[CuN2/2] and isolated units 0[CuN2], and one-dimensional indium clusters 1[In2In4/2] are contained in the structure. A split-site model applied for the arrangement of 1[CuN2/2] chains suggested that there is a short-bond, long-bond alternation of the Cu-N bondings. The electrical resistivity of Ba8Cu3In4N5 was 3.44 mΩ·cm at 298 K. A metallic temperature dependence of the resistivity was observed down to 10 K.  相似文献   

8.
This paper describes the results of electron microscopy, high-temperature powder neutron diffraction, and impedance spectroscopy studies of brownmillerite-structured Ba2In2O5 and perovskite structured Ba(InxZr1−x)O3−x/2. The ambient temperature structure of Ba2In2O5 is found to adopt Icmm symmetry, with disorder of the tetrahedrally coordinated (In3+) ions of the type observed previously in Sr2Fe2O5. Ba2In2O5 undergoes a ∼6-fold increase in its ionic conductivity over the narrow temperature range from ∼1140 K to ∼1230 K, in broad agreement with previous studies. This transition corresponds to a change from the brownmillerite structure to a cubic perovskite arrangement with disordered anions. Electron microscopy investigations showed the presence of extended defects in all the crystals analyzed. Ba(InxZr1−x)O3−x/2 samples with x=0.1 to 0.9 adopt the cubic perovskite structure, with the lattice parameter increasing with x.  相似文献   

9.
Cadmium in Square Pyramids of Oxygen in the Barium Cadmium Oxovanadate: Ba2Cd3(VO4)2(V2O7) Single crystals of Ba2Cd3(VO4)2(V2O7) have been prepared by crystallization of a melt of BaCO3, CdO and V2O5. It shows orthorhombic symmetry, space group D? P212121, a = 7.206(2), b = 9.978(1), c = 19.617(3) Å, Z = 4. The crystal structure is characterized by (VO4)3? and (V2O7)4? groups, CdO6 octahedra, BaO12 and BaO9 polyhedra and with respect to Cd containing oxides unusual square pyramids of O2? around Cd2+. The observed [CdO4] zickzack chains are connected by VO4 tetrahedra, V2O7 double tetrahedra and CdO5 pyramids, forming a tunnel structure along [100]. The tunnels are filled by barium.  相似文献   

10.
On the Oxoargentato(I)-aurat(III): Ba4AgAuO6 The hitherto unknown compound Ba4AgAuO6 was prepared by oxidizing Ba/Au/Ag alloy with BaO2/Ba(OH)2 mixture in closed Ag tubes. X-ray single crystal investigation led to orthorhombic symmetry space group D-Cmcm; a = 13.275; b = 5.782; c = 11.396 Å; Z = 4. Ba4AgAuO6 shows distorted pentagonal bipyramidal polyhedra around Ba2+ and square planar AuO4 polygones. Ag+ shows an unusual 2 + 2 coordination by O2?.  相似文献   

11.
Two New Alkaline-Earth-Oxoindates: BaCa2In6O12 and BaSr2In6O12 The hitherto unknown compounds (I): BaCa2In6O12 and (II): BaSr2In6O12 were prepared and examined by single crystal X-Ray work. (I) and (II) crystallize with hexagonal symmetry, space group C? P63/m, with (I): a = 9.880, c = 3.211 Å; (II): a = 9.9443; c = 3.2671 Å, Z = 1. Both compounds are isotypic to the metastable oxide AM2Ln6O12, but without metastable behavior. The [In6O12]6? network is occupied by the alkaline earth ions. One of the tunnels is stuffed by Ca2+ and Sr2+ respectively, the other one by Ba2+ in a statistical distribution on possible point positions. (I) and (II) prove the existence of the AM2Ln6O12-type in respect to small Ln3+ ions.  相似文献   

12.
On an Oxide Chloride of CoIII: Sr8Co6O15Cl4 Sr8Co6O15Cl4 was prepared for the first time by flux reaction. It crystallizes with tetragonal symmetry: space group D4h17–I4/mmm; a = 3.927; c = 31.429 Å; Z = 1. Co3+ has different coordinations. One point position show CoO6 octahedra, the other one has a CoO5Cl surrounding. An oxygen deficit exhibit partly distorted square pyramids. Sr8Co6O15Cl4 is strongly related to Ba8In6O17.5 or can be seen as Sr4Co3O7.5Cl2 as a variety of the Sr4Ti3O10 type.  相似文献   

13.
The Variation of Properties by Incorporation of Tav in Ba2Gd0.67UO6 In Ba2Gd□0.33UVIO6 the complete substitution of UVI by TaV is only possible by filling up the gadolinium vacancies (Ba2Gd0.67+0.33xU1?xTaxO6), whereas in the series Ba2Gd0.67U1?yTayO6–0.5y the phase boundary is reached with y = 0.1. Depending on x the variation of the properties is studied by X-ray and spectroscopic methods.  相似文献   

14.
Determination of Structures of Ordered Perovskites of the Ba2B MVIO6 Type Intensity calculations on powder patterns of Ba2Y□0.33MVIO6 with MVI = U, W, Te und Ba2Gd0.670.33UO6 lead for the space group Fm3m/O with 8 Ba in 8c, 8/3 BIII and 4/3 □ in 4b, 4 MVI in 4a and 24 O in 24e to R values between 4.3 and 7.6%. Two further models are discussed.  相似文献   

15.
Single crystals of new quaternary compounds Sr8Cu3In4N5 and Sr0.53Ba0.47CuN were prepared, respectively, from a Sr–Cu–In–Na melt under 7 MPa of N2 and from a Sr–Ba–Cu–In–Na melt under 0.5 MPa of N2 by slow cooling from 1023 to 823 K. The crystal structures were determined by single-crystal X-ray diffraction. Sr8Cu3In4N5 has an orthorhombic structure (space group, Immm, Z=2, a=3.8161(5) Å, b=12.437(2) Å, c=18.902(2) Å), and is isostructural with Ba8Cu3In4N5. It contains nitridocuprates of isolated units 0[CuN2] and one-dimensional linear chains 1[CuN2/2] and one-dimensional indium clusters 1[In2In2/2]. Sr0.53Ba0.47CuN crystallizes in an orthorhombic cell, space group Pbcm, Z=4, a=5.4763(7) Å, b=9.2274(12) Å, c=9.0772(12) Å. The structure contains infinite zig-zag chains 1[CuN2/2] which kink at every second nitrogen atom.  相似文献   

16.
On the Polymorphism of In5Br7 The existence of two polymorphs of In5Br7 has been proved by single crystal structure determinations. In5Br7 (tP192) crystallizes with the tetragonal space group P41212 and lattice parameters at = 1318.9(5) pm and ct = 3723.8(9) pm (293 K). Concerning monoclinic In5Br7 (mC192), the centrosymmetric space group C2/c with lattice parameters am = 1867.3(4) pm, bm=1867.0(5) pm, cm = 1918.0(7) pm, and βm = 103.96(2)° (293 K) has been confirmed. Both modifications of In5Br7 are built up from layers of the same type. These layers with a thickness of about 930 pm consist of structure fragments [InBr2]4+ and [InBr12]4–. The anion is composed of two ethan‐like [InBr6]2– units, which contain In–In bonds. The stacking sequence of the layers with symmetry C 1 2 (1) differs for the two modifications of In5Br7. The tetragonal form is generated by applying a 41 screw axis; the monoclinic polymorph is formed by introducing inversion centers between the layers. The adequate name of In5Br7 = In[InBr6]Br is triindium(I)‐hexabromodiindate(II)(In–In)‐bromide.  相似文献   

17.
On a Barium Rare Earth Oxozincate/Platinate(IV): Ba2Eu2ZnPtO8 High temperature reactions of BaCO3, ZnO and Eu2O3 in platinum crucibles led to single crystals of Ba2Eu2ZnPtO8. It crystallizes with orthorhombic symmetry, space group D-Pnma, a = 13.390(1), b = 5.764(1), c = 10.387(1) Å, Z = 4 and is isotypic to Ba2Y2CuPtO8. Ba2Eu2ZnPtO8 is characterized by isolated 1[ZnPtO8]10? anions formed by ZnO5-pyramids and PtO6-octahedra. The space between the [ZnPtO8]10? groups is filled by Eu3+ and Ba2+ ions. Relationships to zinc and platinum containing oxometallates are discussed.  相似文献   

18.
On Osocuprates. XI. Ba3Cu2O4Cl2 A new oxohalogenocuprat, Ba3Cu2O4Cl2 mas prepared and investigated by X-ray single crystal methods. The hitherto unknown compound has orthorhombic symmetry (Space group: D2h5—Pmma; a = 6.653, b = 6.000, c = 10.563 Å). It shows angled chains of O2?-squares around Cu2+. One of the Cu2+ positions is completed by Clminus; to a tetragonal pyramid. The coordination polyhedrals of BaI–III and the connection with the Cu/O-chains are described and discussed.  相似文献   

19.
IrIn7GeO8 = [IrIn6](GeO4)(InO4) and Compounds of the Solid Solution Series [IrIn6](Ge1+xIn1?4x/3O8) (0 ≤ x ≤ 0.75): First Oxides containing [IrIn6] Octahedra The low valent indiumoxides IrIn7GeO8 = [IrIn6](GeO4)(InO4) and [IrIn6](Ge1+xIn1?4x/3O8) (0 x ≤ 0.75) are formed by heating intimate mixtures of Ir, In, In2O3 and GeO2 in corundum crucibles under an atmosphere of argon (1420 K, 70 h). The compounds are black and semiconducting. X‐ray powder diffraction patterns can be indexed on the basis of a face centered cubic unit cell with lattice parameters ranging from a = 1012.3(1) pm (x = 0) to a = 1007.3(1) pm (x = 0.75). Characteristic building units in [IrIn6](Ge1+xIn1?4x/3O8) are isolated [IrIn6]9+ octahedra with short Ir‐In distances of 253.5 pm, which are linked via [GeO4]4? and [InO4]5? tetrahedra to a three dimensional framework. Starting from IrIn7GeO8 = [IrIn6](GeO4)(InO4), the isoelectronic substitution of 4 In3+ ions by 3 Ge4+ ions and one Ge‐vacancy leads to the formation of a solid solution series [IrIn6](GeO4)1+x(O4)x/3(InO4)1?4x/3, which shows a slight decrease in the cubic lattice parameter with increasing x. According to Rietveld refinements the structure of [IrIn6](GeO4)(InO4) exhibits a statistical distribution of the tetrahedrally coordinated Ge and In atoms ( , R(prof.) = 4.4 %, R(int.) = 2.5 %). The crystal and electronic structures of [IrIn6](GeO4)(InO4) are discussed on the basis of first principles electronic structure calculations.  相似文献   

20.
Tetrahedral Polycations [In5]7+ in ‘‘Na23In5O15”︁”︁ (=Na24In5O15?) an Unusual Oxidation Product of the Alloy NaIn The already published, red-transparent, air sensitive, cubic compound Na24In5O15 (a = 1107.7 pm, Z = 2, I43m) is an intermediate oxidation product of the intermetallic phase NaIn. It is reinvestigated with respect to the question whether it contains the tetrahedral polycation [InIn4]6+ or [InIn4]7+. In the latter case the chemical composition would be Na23In5O15 instead of Na24In5O15 and the polycation would be in accordance with the Zintl-Klemm concept. Na24In5O15 is prepared in single phased samples for the first time and investigated by means of the Rietveld refinement technique of X-ray powder data. Based on the results of the Rietveld refinements and new single crystal data in comparison to the published values we note anomalies in the occupancies of the Na positions and a pronounced anisotropy in the thermal parameters of one oxygen position. These investigations together with results obtained by analytical scanning electron microscopy, Extended Hückel and MAPLE calculations give strong evidence for the assumption of [InIn4]7+ instead of [InIn4]6+ and the associated correct composition Na23In5O15. The problems of a reliable characterization of this unique compound are discussed.  相似文献   

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