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1.
The phase relations in the In2O3Fe2O3CuO system at 1000°C, the In2O3Ga2O3CuO system at 1000°C, the In2O3Fe2O3CoO system at 1300°C, and the In2O3Ga2O3CoO system at 1300°C were determined by means of a classical quenching method. InFeCuO4 (a = 3.3743(4) Å, c = 24.841(5) Å), InGaCuO4 (a = 3.3497(2) Å, c = 24.822(3) Å), and InGaCoO4 (a = 3.3091(2) Å, c = 25.859(4) Å) having the YbFe2O4 crystal structure, In2Fe2CuO7 (a = 3.3515(2) Å, c = 28.871(3) Å), In2Ga2CuO7 (a = 3.3319(1) Å, c = 28.697(2) Å), and In2FeGaCuO7 (a = 3.3421(2) Å, c = 28.817(3) Å) having the Yb2Fe3O7 crystal structure, and In3Fe3CuO10 (a = 3.3432(3) Å, c = 61.806(6) Å) having the Yb3Fe4O10 crystal structure were found as the stable ternary phases. There is a continuous series of solid solutions between InFeCoO4 and Fe2CoO4 which have the spinel structure at 1300°C. The crystal chemical roles of Fe3+ and Ga3+ in the present ternary systems were qualitatively compared.  相似文献   

2.
X-Ray Structure of [{LiOC6H2-2,4,6-(CH3)3}4(THF)3] The title compound crystallized from a THF/OEt2 solution. Its crystal structure (monoclinic, P21/c, a = 21.362(3), b = 13.441(2), c = 17.188(2) Å, β = 98.39(1)°, Z = 4, R = 0,0911, wR2 = 0,2562) is built up by cuban-like tetrameric units. Three of the four Li cations attain a coordination number of four by binding to an additional THF molecule. Li(4) without THF coordination has a short distance to one ortho-methyl group (Li(4)…C(27) 2.669(10) Å). The Li–Oph bonding distances vary from 1.869(10) to 2.051(10) Å (average 1.97 Å); the average bonding distance for Li–OTHF is 2.012(10) Å. Averaged bonding angles for Li–Oph–Li′ and Oph–Li–O′ph amount to 84.4(4)° and 95.4(4)°, respectively. The Li…Li distances significantly differ from each other. They range from 2.556(12) to 2.739(11) Å (average 2.65(1) Å).  相似文献   

3.
Preparation and Crystal Structure of Lead(II) Monoglycerolate Crystals of lead(II) monoglycerolate, of a quality suitable for diffraction studies, have been prepared from an alkaline plumbate solution and an excess of glycerol. The compound crystallizes in the monoclinic space group P21/c with a = 5.617(6) Å, b = 9.471(8) Å, c = 9.726(7) Å, β = 102.65(11)°. The structure was refined by full matrix least-squares techniques to an R value (1026 F0) of 0.078. The compound to which the formula Pb(C3H6O3) could be assigned, is polymeric in one direction. The lead and a part of the oxygen atoms built up a zig-zag chain parallel to the aaxis. The oxygen form a distorted tetragonal pyramid with lead at the apex. A decomposition temperature of 235°C has been determined.  相似文献   

4.
On the Low Temperature Modifications of Ag6Si2O7 and Ag6Ge2O7 – Synthesis, Crystal Structure, and Comparison of Ag? Ag Distances For the first time, single crystals of Ag6Si2O7 and Ag6Ge2O7 have been obtained by solid state reactions of the binary oxides at temperatures of 350°C while applying oxygen pressures of 700 bar. According to the results of X-ray crystal structure determinations both compounds crystallize isostructural in P21 (Ag6Si2O7: a = 5.3043(5) Å, b = 9.7533(7) Å, c = 15.9283(13) Å, β = 91.165(8)°, 3881 independent reflections, R1 = 3.3%, wR2 = 7.2%; Ag6Ge2O7: a = 5.3713(4) Å, b = 9.9835(8) Å, c = 16.2249(14) Å, β = 90.904(8)°, 2111 independent reflections, R1 = 4.3%, wR2 = 6.0%, Z = 4). The crystal structures contain two independent M2O76? anions, one in a staggered, and the other in an ecliptic conformation. The cationic partial structure may be described as a distorted bcc arrangement of Ag+ and M4+. Comparison of the structures with respect to the Ag? Ag separations reveals the latter to be probably due to intrinsic d10–d10 bonding interactions as far as the range of 2.89 Å to 3.25 Å is considered.  相似文献   

5.
Synthesis and Structure of Cs11[(WN2,5O1,5)2](N3)2, a Cesium Oxo Nitrido Monotungstate(VI) Azide Cs11[(WN2,5O1,5)2](N3)2 results from the reaction of a mixture of CsNH2, W and WO3 at 620 °C in autoclaves. It crystallizes monoclinic in the space group C2/m with the lattice parameters a = 12.421(4) Å, b = 11.568(6) Å, c = 10.516(4) Å, β = 118.71(3)° and Z = 4. The crystal structure is built up by isolated tetrahedra [WX4] with X = N, O, which are connected by cesium cations. Between the cesium ions lie azide ions separated from the anions [WX4]. The tungsten atoms and azide ions together build up the motif of a distorted arrangement of the CsCl structure type.  相似文献   

6.
《Solid State Sciences》1999,1(6):373-380
Na2CaP2O7 has been prepared in single crystal form by fusion techniques. The single crystal structure: a = 5.361(3), b = 7.029(3), c = 8.743(4)Å, α = 69.40(2), β = 89.02(3), γ = 88.78(4) °, V = 308.5(3)Å3, space group P1 bar, Z = 2, Dcalc = 2.799 mg/m3, R/Rw = 0.0445/0.0554 for 1434 observed reflections (F>4.0σ(F), shows a solid state form similar to that of K2SrP2O7, K2MnP2O7 and KaCdP2O7.  相似文献   

7.
In the view of synthesizing microporous composite compounds, the ternary systems NH4VO3: alkyldiphosphonic acid:H2O were hydrothermally investigated. Using the methylendiphosphonic acid, the mixture corresponding to the molar ratio 1:0.3:500 heated three days at 200 °C, leads to small platelets whose structure was determined by single crystal X-ray diffraction. Their symmetry is orthorhombic (space group Pnma (n° 62)) with lattice parameters: a = 7.3182(1) Å, b = 16.5633(1) Å, c = 7.5225(2) Å, V = 911.83(4) Å3, Z = 4. The compound labelled MIL-10, is formulated VIVO{O3P-CH2-PO3}(NH4)2, and shows a monodimensional structure characterized by the presence of polyhedral chains between which ammonium cations are located. The isostructural titanium compound was also hydrothermally synthesized. Its structure was solved from single crystal data; its symmetry is orthorhombic (space group Cmcm (n° 63)) with lattice parameters: a = 16.462(1) Å, b = 7.7671(6) Å, c = 7.2830(6) Å, V = 931.2(1) Å3, Z = 4.  相似文献   

8.
The Eu? Bi system contains the phases Eu5Bi3, Eu4Bi3 and Eu11Bi10. The structure types of these phases have been determined by powder X-ray diffraction. Crystals of Eu4Bi3 (cubic, space group I4 3d; a = 9.920 Å, Z = 4, T = 130 K, R1/wR2 = 4.86/10.84%) were obtained in low yield by reaction of Eu, Mn, and Bi in the ratio 14:1:11 in a closed niobium tube (heating rate 30°C/h; reaction at 1050°C for 300 h, cooling rate 100°C/h). The crystal structure consists of distorted octahedra made up of six Bi coordinated to a central Eu atom. Eu is also coordinated to a three other Eu atoms and forms a three-dimensional network composed of interconnected rings. The Bi atoms are coordinated to eight Eu atoms. High yields of Eu4Bi3 can be prepared by reacting stoichiometric amount of the elements in a sealed tantalum tube at 1100°C for 24 h. Temperature dependent magnetic susceptibility is consistent with antiferromagnetic behavior with an ordering temperature of 18 K. The data could be fit with the Curie-Weiss law and a moment of 7.38 μB/Eu is obtained, consistent with all Eu atoms being Eu11. Temperature dependent resistivity indicates that Eu4Bi3 is a metal with a room temperature resistance of 1.3 Ωcm.  相似文献   

9.
Synthesis, Crystal Structure, and Properties of Copper(II) Ultraphosphate CuP4O11 CuP4O11 was synthesised from Cu2P4O12 and P4O10 (500°C, sealed silica ampoules) using iodine and a few mg of CuP2 or phosphorus as mineraliser. Chemical transport reactions in a temperature gradient 600 → 500°C led to the formation of well developed, colourless, transparent crystals with edge-lengths up to 5 mm (deposition rate m ≈? 2 mg/h). The crystal structure of copper(II) ultraphosphate (C1 ; Z = 8; a = 13.084(3) Å, b = 13.024(2) Å, c = 10.533(2) Å, α = 89.28(2)°, β = 118.42(2)°, γ = 90.30(2)°) has been determined and refined from X-ray data obtained from a pseudo-merohedrally twinned crystal (twin element two-fold rotation axis // b; volume ratio: 17/3; 3063 independent reflections with 2θ ? 53.4°; 291 variables; conventional residual (based on F) R1 = 0.038, wR2 = 0.101 (based on F2), GooF = 1.10). The crystal structure of CuP4O11 is built from four crystallographically independent ten-membered polyphosphate rings of very similar conformation. These rings are linked to form two-dimensional nets parallel (?2 0 1) planes. There is a close topological relationship between these nets and those formed in polyphosphides CdP4 and CuP2. Copper on two crystallographic sites (Cu2P8O22) is coordinated by oxygen thus forming elongated [CuO6] octahedra (deq(Cu? O) ≈? 1.96 Å; dax(Cu? O) ≈? 2.34 Å). The crystal g-tensor of CuP4O11 has been determined from powder samples to g1 = 2.09, g2 = 2.24, g3 = 2.36. These values are in good agreement with molecular g-values from calculations within the framework of the angular overlap model on the two independent CuO6 octahedra (Cu2+(1): gx = 2.09, gy = 2.10, gz = 2.52; Cu2+(2): gx = 2.08, gy = 2.11, gz = 2.52) assuming exchange coupling. The observed broad absorption band (7000 cm?1 to 13000 cm?1) from powder reflectance measurements (4000–28000 cm?1) and the bulk magnetic susceptibility of μexp = 1.99 μB is also reproduced nicely by this calculations.  相似文献   

10.
Crystal Structure of Pb13O10Br6, a New Lead Oxidehalide Strongly yellow Pb13O10Br6 was prepared for the first time and the crystal structure was explored by single crystal measurement. The compound crystallizes with monoclinic symmetry in space group C2/c—No. 15 with a = 16.439(6) Å, b = 7.163(1) Å, c = 23.940(9) Å, β = 98.39(3)° and four formulas per unit cell. The structure was refined by full matrix least-squares techniques to Rw = 0.0727 (2 030 reflections with I ≥ 3σ(I), MoKα, 4-circle-diffractometer AED2). Regions of lead(II) oxide exists within the structure, which are separated from the content of bromide. Pb13O10Br6 is a connecting link between oxidehalides and the tetragonal modification of PbO.  相似文献   

11.
The colorless Cs4ZrO4 is obtained from the reaction of stoichiometric proportions of Cs, CsO2, and finely divided ZrO2 in a sealed Ag container at 400–650°C for several days. Regrinding and re-reaction provide a single phase sample. The compound is monoclinic (P21/c, Z = 4, a = 7.172 (1) Å, b = 19.907 (1) Å, c = 7.157 (1) Å, β = 113.1 (1)Å, R = 0.032) and isostructural with Cs4PbO4, with isolated ZrO44? tetrahedra (d(Zr–O) = 1.97 Å). The compound decomposes to Cs2ZrO3 (a) in the presence of excess oxygen or CsO2, (b) in high vacuum near 275°C, or (c) in a sealed container at about 730 ± 10°C.  相似文献   

12.
A new phase, BaNb6.3(1)Ti3.6(1)O16, has been synthesised. Electron diffraction studies indicate an hexagonal substructure with unit cell parameters a ≈ 8.9 Å and c ≈ 9.5 Å. In some of the ED patterns superstructure reflections are present, indicating a supercell with a = √3 · asub and c = csub. However, X‐ray single‐crystal diffraction studies of a crystallite yielding reflections corresponding to the supercell revealed it to be monoclinic, with the unit cell parameters a = 26.811(2) Å, b = 15.4798(2) Å, c = 9.414(2) Å, β = γ = 90° and α = 90.0(3)°. The average crystal structure was refined, using the subcell with a = 8.937(2) Å, b = 15.479(2) Å, c = 9.414(2) Å, β = γ = 90° and α = 90.0(3)°, space group Cm11, and Z = 4, to RI = 3.24% and RwI = 3.44%. The structure can be described as an hexagonal close packing layers of Nb6 octahedra, Ba, and O atoms (A1, A2) and layers of O atoms (B1, B2), appearing in the packing sequence: A1B1A2B2. The Nb6 octahedra are found in isolated Nb6O12O6 clusters, and the Ti atoms in Ti3O13 and Ti3O10 units in octahedral and tetrahedral voids formed by O atoms, respectively. The Ti positions were found to be only partly occupied. Microanalysis indicates that some Nb atoms are located in the Ti3 triangles. A model is presented that interprets these not fully occupied Ti3 triangles as a result of a superimposing of three different structures. Two of these consist of two fused Ti3O13 units, forming an Ti6O19 unit, and a Ti3O10 unit, while the third consists of alternating Ti3O13 units.  相似文献   

13.
We have found a new compound Mn8O10Cl3. It is prepared by oxidation of anhydrous or hydrated MnCl2 in streaming (N2 + O2) at temperatures less than 680°C. At room temperature the compound is tetragonal, a = b = 9.2898 Å, c = 13.0247 Å. The more symmetric space group is I4mmm. Mn8O10Cl3 becomes cubic at 360°C with the c-axis as cubic parameter. In air, DTA and GTA have shown that Mn8O10Cl3 is transformed at 580°C into Mn2O3 which gives Mn3O4 at 960°C. The exact formula has been determined only by crystal structure analysis.  相似文献   

14.
Two new organically templated borates, [H2DAB][B7O9(OH)5]·2H2O ( 1 ) and [H2DAB][B7O10(OH)3] ( 2 ), have been synthesized under mild conditions in the presence of DAB acting as structure‐directing agent (DAB = 1,4‐diaminobutane). The structures were determined by single crystal X‐ray diffraction and further characterized by FTIR, elemental analysis, and thermogravimetric analysis. Both 1 and 2 crystallize in the same triclinic system, space group (No. 2); 1: a = 8.238(4) Å, b = 8.348 (5) Å, c = 14.574(8) Å, a = 101.050(3)°, β = 92.313(7)°, γ = 112.694(5)°, V = 900.3(8) Å3, Z = 2; 2: a = 8.8769(3) Å, b = 9.3204(2) Å, c = 10.2204(5) Å, α = 74.474(2)°, β = 85.292(5)°, γ = 72.730(2)°, V = 778.01(5) Å3, Z = 2. The structure of 1 consists of [B7O9(OH)5]2? groups, which represents the first example of organically templated heptaborate. The structure exhibits interesting hydrogen‐bonded network formed by borate polyanion [B14O20(OH)6]4?, which can be regarded as being constructed from the dehydration of the FBBs in 1 . The diprotonated organic amines are filled in the free space of the hydrogen‐bonded network and interact with the inorganic framework by extensive hydrogen bonds.  相似文献   

15.
Compound formation in the system PbGeO3? Pb5Ge3O11 was studied by thermal analysis and high-temperature X-ray diffraction. New modifications of PbGeO3 and Pb5Ge3O11 were prepared by the simultaneous hydrolysis of lead and germanium alkoxides, followed by washing and drying; the former has a hexagonal unit cell with a = 15.573 Å and c = 7.240 Å, and the latter has an orthorhombic crystal structure with a = 5.081 Å, b = 7.301 Å and c = 8.817 Å. They are transformed to the known monoclinic and hexagonal modifications at 575 to 610°C and 410 to 450°C, respectively. No compound of Pb3Ge2O7 was confirmed. The structures of germanate groups in the lead germanate compounds are discussed on the basis of the infrared spectral data.  相似文献   

16.
Contributions to the Thermal Behaviour of Sulfates. III. The Behaviour of CdSO4 at High Temperature The behaviour of CdSO4 was studied by means of high temperature Guinier photographs in the temperature range of 20 to 960°C. Except N-CdSO4 which is the thermodynamically stable modification at STP, there are 3 high temperature modifications (M, H1 and H2-CdSO4) of which only metastable M-CdSO4 can be obtained kineticly stable at room temperature. The lattice constants and the structure type of H1- and H2-CdSO4 were determined. The structure of H1-CdSO4 is closely related with that of N-CuSO4 but in difference of N-CuSO4 it has a superlattice. H1-CdSO4 crystallizes orthorhombic with a325°C = 17.80 Å, b325°C = 7.35 Å, c325°C = 4.84 Å, Z = 8.H2-CdSO4 crystallizes hexagonal with a850°C = 5.01 Å, c850°C = 7.64 Å, Z = 2 in a modified NaKSO4 structure type (space group P 3 m 1) with Cd2+ only in the Na+ positions. The temperatur and sequence of transitions as well as the thermal expansion of N- and M-CdSO4 was determined  相似文献   

17.
Rb6Mn2O6 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursors (Mn3O4, RbN3 and RbNO3) were heated in a special regime up to 500 °C and annealed at this temperature for 75 h in silver crucibles. Single crystals have been grown by annealing a mixture with a slight excess of rubidium components at 450 °C for 500 h. According to the single crystal structure analysis, Rb6Mn2O6 is isotypic to K6Mn2O6, and crystallizes in the monoclinic space group P21/c with a = 6.924(1) Å, b = 11.765(2) Å, c = 7.066(1) Å, β = 99.21(3)°, 2296 independent reflections, R1 = 5.23 % (all data). Manganese is tetrahedrally coordinated and two tetrahedra are linked by sharing a common edge, forming a dimer [Mn2O6]6−. The magnetic behavior has been investigated.  相似文献   

18.
Ag2Pb8O7Cl4, a New Member of Lead(II) Oxyhalides with Silver Ag2Pb8O7Cl4 is one among other products of the thermal decomposition of AgPb4O4Cl. Ag2Pb8O7Cl4 can be prepared directly by heating the binary components within a temperature range from 590°C to 620°C. The crystal structure was solved by single crystal X-ray methods. The compound crystallizes monoclinic with a = 12.411(4) Å, b = 17.99(3) Å, c = 14.785(4) Å, β = 147.01(2)°, Z = 4 with the space group P21/c. Ag2Pb8O7Cl4 shows remarkable structural features, e.g. silver tetrahedrally surrounded by chlorine.  相似文献   

19.
Structure‐Behaviour‐Relation of Cu5Pb6O3Cl11, a Good Solid State Ionic Conductor for Cu+‐Ions A new compound within the group of coin metal lead(II) oxide halides is found and characterized by X‐ray single crystal structure determination in a temperature range from 120 K to 400 K. Cu5Pb6O3Cl11 shows a new crystal type structure with a = 21.098(4) Å, b = 10.233(2) Å, c = 12.224(2) Å, β = 124.08(3)°, Z = 4 and space group C 2/c (No. 15) at 120 K. There are found isolated oxidic chains built of OPb4 tetrahedra beside columnar areas consisting of CuCl. In this halidic partial structure are a lot of empty and partially occupied Cl4‐tetrahedra. This structural characteristic seems to be source of a very good conductivity of copper ions, like in microscopic and nanoscaled composites of Al2O3 and AgI.  相似文献   

20.
Crystal Structures of Acid Hydrates and Oxonium Salts. XX. Oxonium Tetrafluoroborates H3OBF4, [H5O2]BF4, and [H(CH3OH)2]BF4 The crystal structures of three oxonium tetrafluoroborates were determined. H3OBF4, oxonium tetrafluoroborate proper, is triclinic with space group P1 , Z = 2 and the unit cell dimensions a = 4.758, b = 6.047, c = 6.352 Å and α = 80.40, β = 79.48, γ = 88.25° at ?26°C. Cations H3O+ and anions BF4? are linked by hydrogen bonds O? H…?F into ribbons of condensed rings. In [H5O2]BF4 (diaquohydrogen tetrafluoroborate, monoclinic, P21/c, Z = 4, a = 6.584, b = 9.725, c = 7.084 Å, β = 95.15° at ?100°C) the hydrogen bond in the cation H5O2+ is 2.412 Å short, asymmetric and approximately centered and the linking of cations and anions three-dimensional. In [H(CH3OH)2]BF4 (Bis(methanol)hydrogen tetrafluoroborate, monoclinic, P21/c, Z = 4, a = 5.197, b = 14.458, c = 9.318 Å, β = 94.61° at ?50°C) the cation [H(CH3OH)2]+ is characterized for the first time in a crystal structure with an again very short (2.394 Å), asymmetric and effectively centered hydrogen bond. By further hydrogen bonds cations and anions form only dimers of the formula unit of centrosymmetric cyclic structure.  相似文献   

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