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1.
We discovered that reactions of hydrous cobalt and zinc acetates with 3,5-dimethylpyrazole (Hdmpz) in boiling xylene or toluene or upon the thermolysis of solid precursors (150°C) yield trinuclear pyrazolate-bridged complexes M3 (μ-dmpz)4(Hdmpz)2 (OOCMe)2(M = Zn or Co). Depending on the crystallization conditions, these complexes contain various solvating molecules (benzene, toluene, or Hdmpz), which influences the character of intramolecular and intermolecular hydrogen bonding, as shown by X-ray crystallography.  相似文献   

2.
Perovskite-like phases AMn3V4O12 (A = Ca, Ce, and Sm) were prepared under borothermic conditions (p = 7.0–9.0 GPa, T = 700–1100°C). Their X-ray diffraction structure (space group Im \(\bar 3\), Z = 2) was determined, and unit cell parameters were calculated: for CaMn3V4O12: а = 7.40824(3) Å, for SmMn3V4O12: а = 7.45280(8) Å, and for CeMn3V4O12: а = 7.46965(4) Å. The temperature-dependent electrical resistivity (10–300 K) and magnetic susceptibility (2–300 K) of the prepared phases were studied.  相似文献   

3.
Organometallic polymers MF3(4,4′-Bipy) with M = Ga and In are synthesized by the hydrothermal method. According to X-ray diffraction data, in a metal atom in the polymeric structure is octahedrally coordinated by four fluorine atoms and two nitrogen atoms. Bridging fluorine atoms and bidentate-bridging 4,4′-Bipy molecules join the complexes into layers.  相似文献   

4.
Triethylamine reacts with aqueous zinc acetate and the product of its thermolysis in the presence of benzoic acid to yield the complexes [Zn74-O)(μ-OOCMe)10][η-OC(Me)OHNEt3]2 (1) and [Zn2(μOOCPh)4][η-OC(Me)OHNEt3]2 (2), respectively. The reactions of 1 and 2 with 3,5-dimethylpyrazole at room temperature in benzene yield pyrazolate-bridged binuclear complexes Zn2(μdmpz)2(Hdmpz)2(OOCR)2 (R = Me (3), Ph (4)). The structures of complexes 1–4 have been determined by X-ray crystallography.  相似文献   

5.
Synthesis of (Sr, Ba)4Э2Nb2O11 ± δ where E = Mn, Cr, Cu and solid solution (Sr1?y Cuy)6 ? 2x Nb2 + 2x O11 + 3x is performed. By measuring the overall conductance of some solid-solution compositions it is established that the conductance increases with the cubic-lattice parameter and concentration of oxygen vacancies. Values of the conductance in humid air at T < 700°C are shown to increase as compared with dry air. Mass spectrometry analysis confirms the possibility of water incorporation into the complex-oxide structure out of a gas phase. Complex certification of samples of the composition (Sr, Ba)4E2Nb2O11 where E = Mn, Cr, Cu is performed. It is established that the decrease in the overall electroconductance occurs in the series Sr4Mn2Nb2O11 > Ba4Mn2Nb2O11 > Sr4CrMnNb2O11 > Sr4Cu2Nb2O11. Investigation of the overall electroconductance in dry and moist atmospheres shows that the effect of humidity exerts no influence on the values of the overall electroconductance. The oxygen-ion constituent of conductance is determined by the Arzhannikov method and is also evaluated from a σ,pO2 dependence. It is established that the presence of an element with a variable oxidation degree for compositions of the type Sr4E2Nb2O11 leads to an increase in the contribution made by the electronic constituent. In so doing, the magnitude of the oxygen-ion conductance practically does not alter. Thermal and mass spectrometry analyses show that, for the Sr4E2Nb2O11 compositions where E = Mn, Cr, Cu, there occurs no water intercalation into structure, correspondingly, there is observed no appearance of a protonic constituent of conduction.  相似文献   

6.
[Ln(H2O)8][Cr(NCS)6] · 5H2O aqua complexes, where Ln = Er (1), Lu (2), have been found in an aqueous solution instead of binary complex salts with an organic ligand in their cation, when crystal products of the reaction between Ln(NO3)3 · 6H2O (Ln = Er, Lu), K3[Cr(NCS)6] · 4H2O, and 8-oxyquinoline (C9H7NO) were studied by X-ray diffraction. Crystals of complexes 1 and 2 are isostructural and crystallize in triclinic system, space group P\(\bar 1\), Z = 2. For complex 1: a = 9.0677(4) Å, b = 9.3115(4) Å, c = 16.9595 Å, α = 81.526(2)°, β = 86.153(2)°, γ = 83.879(2)°, V = 1406.33(10) Å3, ρcalc = 1.894 g/cm3; for complex 2: a = 9.0438(3) Å, b = 9.2880(3) Å, c = 16.9181(3) Å, α = 81.7250(10)°, β = 86.1600(10)°, γ = 83.8850(10)°, V = 1396.38(7) Å3, ρcalc = 1.926 g/cm3.  相似文献   

7.
Crystals of MCl2·2CONH3 (M = Cu2+, Mn2+) are synthesized from low-temperature water-formamide solutions and studied by crystal optical, single crystal X-ray diffraction, and infrared spectroscopy methods. The crystal structures of CuCl2·2CONH3 and MnCl2·2CONH3 are solved by direct methods and refined in the P1triclinic space group, R1= 0.043 and 0.038 for 501 and 686 reflections with F 0ÃΣ(F0) respectively. Unit cell parameters for Cu and Mn salts are: a = 3.705(1) Å and 3.685(1) Å, b = 7.049(2) Å and 7.136(2) Å, c = 7.375(2) Å and 7.779(2) Å, 6h =113.57(3)² and 117.17(2)², β = 96.17(3)² and 95.35(2)², γ = 94.85(3)² and 92.23(2)² respectively, Z= 1. In the studied crystal structures, MCl4O2 octahedra share Cl-Cl edges and form chains along the [100] direction. This direction corresponds to a morphological elongation of the obtained crystals and orientation of the maximum refractive index. The FT infrared spectra obtained in a range from 4000 cm?1 to 300 cm?1 are very close to the spectrum of liquid formamide, but exhibit better resolution of absorption bands.  相似文献   

8.
The reaction of Ca(BH4)2 · 1.5Dg with decaborane-14 in diglyme at 85°C yields Ca(B11H14)2 · 4Dg. The duration of the reaction is 20 h. The molar ratio of Ca(BH4)2 · 1.5Dg: B10H14 is 1: 3.5. The yield is 84.7%. The synthesized calcium tetradecahydroundecaborate Ca(B11H14)2 · 4Dg is a stable compound soluble in water and a number of organic solvents. The study of the compound was carried out using elemental analysis and IR and NMR 11B {1H} spectroscopy. Calcium undecaborate can be used for synthesizing other salts with boron hydride nido-borates.  相似文献   

9.
The structural data for single crystals of (Na0.5R0.5)MO4 and (Na0.5R0.5)MO4:R′ (R = La, Gd; R′ = Er, Tm, Yb; M = W, Mo) grown by the Czochralski method were studied by X-ray diffraction and analyzed. The structural characteristics of these compounds depend on the sort of cations M and R. The formation of superstructures was found in the scheelite structure, and distortion of the scheelite structure depending on the composition and preparation conditions was established (with unit cell rotation by 45° and triclinic distortion of the scheelite structure for (Na0.5Gd0.5)WO4:Tm, with doubled unit cell compared to the scheelite type structure for (Na0.5Gd0.5)WO4 and (Na0.5Gd0.5)WO4:Yb). In the case of overstoichiometric oxygen content in the crystal, the unit cell symmetry increases to space group I41/amd or (Na0.5Gd0.5)WO4:Yb without considerable change in the cell parameters. On the basis of experimental data, a transformation scheme for the structures in the system Na 2 + M6+O4?-“R3+M5+O4” was proposed.  相似文献   

10.
A novel organic-inorganic hybrid compound based on weak intermolecular interactions formulated as Ni(H2Bibzim)3Cl2 · 2H2O (H2Bibzim = 2,2-bibenzimidazole, formula, C14H10N4) has been synthesized under hydrothermal conditions and characterized by elemental analysis, single-crystal X-ray diffraction analyses, and IR spectra. It crystallizes in the orthorhombic system, space group Pbcn, Z = 2, a = 20.8530(19), b = 15.7838(14), c = 12.3159(11) Å, V = 4053.7(6) Å3, M r = 1736.84, ρc = 1.423g/cm3, λ = 0.71073 Å, μ(MoK α) = 0.664 mm?1, F(000) = 1792, R = 0.0283 and wR = 0.0707 for 3746 observed reflections with I > 2σ(I). The complex is composed of mononuclear cations [Ni(H2Bibzim)3]2+, chlorine anions, and lattice water molecules, which are linked into a two-dimensional supramolecular architectures via hydrogen bonds and π-π-stacking interactions.  相似文献   

11.
The conduction and transport numbers of charge carriers for composites in the systems MeWO4-WO3 (Me = Ca, Sr, Ba) are studied as a function of the temperature and the activity of oxygen in a gas phase. The transport numbers are determined by an emf method and are estimated from dependences of conductance on the activity of oxygen in a gas phase. The deficiencies of the given procedure as applied to investigation of properties of composite phases are analyzed. The materials under study are classified with a class of metacomposites. The concentration intervals of the ionic, mixed, and electronic conductions are determined. The conduction of composites of compositions (100 − x)MeWO4xWO3 is predominantly ionic at x ≤ 10 (Me = Ca), x ≤ 60 (Me = Sr), and x ≤ 45 (Me = Ba). The obtained data are explained in the framework of a model that represents a composite as a distributed matrix system where a film of surface phase MeW-s with a high mobility of oxygen ions plays the role of a connected matrix. It is presumed that the surface phase MeW-s possesses double-sided surface activity (α MeW-s ≤ ) and a higher mobility with respect to MeWO4 and WO3. The discovered anomalies of dependences (T) and partial dependences , σel(T) are explained by a change in the stoichiometry, morphology, and the degree of connectedness of surface phase MeW-s caused by with a change in the temperature and composition of composites.__________Translated from Elektrokhimiya, Vol. 41, No. 6, 2005, pp. 680–693.Original Russian Text Copyright © 2005 by Neiman, Pestereva, Sharafutdinov, Kostikov.Published on the basis of a report delivered at the VII Meeting on Fundamental Problems in Solid-State Ionics (Chernogolovka-2004).  相似文献   

12.
[Na(H2O)4][EuL4] · 0.775CH2Cl2 (I) has been synthesized by the reaction of Eu(NO3)3 · 6H2O with 1,3-bis(1,3-dimethyl-1H-pyrasol-4-yl)-1,3-propanedione (HL) in the presence of NaOH. Its crystal structure has been solved by X-ray diffraction analysis. Crystals are tetragonal; a = 16.2401(5) Å, c = 11.9113(4) Å, V= 3141.50(17) Å3, ρcalcd = 1.427 g/cm3, μ(MoK α) = 1.140 mm?1, space group P4/n, Z = 2. The structural units forming a crystal of compound I are [EuL4]? complex anions, [Na(H2O)4]+ cations, and CH2Cl2 molecules. The coordination polyhedron of the Eu atom is an Archimedean antiprism formed by the O atoms of four bidentate chelate ligands L?.  相似文献   

13.
The tetranuclear cluster rhenium complexes Cs3H[Re4Q4Cl12] · 3.33H2O (Q = Te (I) and Se (II)) with the Cl atoms as terminal ligands were obtained and structurally characterized. The structures of complexes I and II were determined by X-ray diffraction analysis. Their isostructural crystals are monoclinic; space group C2, Z = 6; a = 26.403(8) Å, b = 16.495(5) Å, c = 11.744(3) Å, β = 91.25(2)°, V = 5113(2) Å3 (I); a = 26.573(3) Å, b = 16.461(3) Å, c = 11.726(2) Å, β = 91.381(4)°, V = 5127.6(14) Å3 (II).  相似文献   

14.
A new metal-organic coordination polymer Cu3(Mip)4(2,2′-Bipy)2 (I), where H2Mip = 5-methylisophthalic acid, 2,2′-Bipy = 2,2′-bipyridine has been hydrothermally synthesized and characterized by IR, elemental analysis, single-crystal X-ray diffraction analysis, and powder X-ray diffraction. The X-ray diffraction analysis reveals that I crystallizes in the triclinic crystal system, space group P \(\bar 1\) and exhibits a one-dimensional chain structure, which contains a trinuclear [Cu3(Mip)2(HMip)2(2,2′-Bipy)2] subunit, and the adjacent subunits are bridged by Mip anions into a 1D chain. Unit cell parameters for I: a = 10.239(2), b = 11.249(2), c = 11.971(2) Å, α = 82.01(1)°, β = 65.03(2)°, γ = 84.32(2)°, V = 1236.5(4) Å3, Z = 2.  相似文献   

15.
LnBaCuCoO5 + δ (Ln = Y, Dy) cuprocobaltites were prepared. Their unit cell parameters were determined and their thermal expansion, electrical conductivity (σ), and Seebeck coefficient (S) were studied in air in the range 300–1100 K. The compounds have tetragonal structures (space group P4/mmm). Their unit cell parameters are a = 0.3867(2) nm, c = 0.7550(7) nm, V = 112.9(2) × 10?3 nm3 for YBaCuCoO4.98; and a = 0.3872(2) nm, c = 0.7562(7) nm, V = 113.4(2) × 10?3 nm3 for DyBaCuCoO5.01. They are p-type semiconductors. The electrical conductivity of DyBaCuCoO5 + δ is slightly lower and its Seebeck coefficient is 1.5–2 times higher than the respective values for YBaCuCoO5 + δ apparently because of different electronic configurations of the rare-earth cations in LnBaCuCoO5 + δ (4d 0 for Y3+ and 4f 9 for Dy3+). Dilatometric measurements show that the LnBaCuCoO5 + δ phases in the range 300–1100 K do not experience structural phase transitions, and their linear thermal expansion coefficients (LTEC) are 14.3 × 10?6 K?1 for Ln = Y and 14.7 × 10?6 K?1 for Ln = Dy.  相似文献   

16.
The formation conditions and physicochemical properties of binary decavanadates M4Na2V10O28 · 10H2O (M=K, Rb, NH4), synthesized by crystallization from saturated solutions of the NaVO3-MH2AsO4-H2O systems, were studied by chemical analysis, X-ray powder diffraction, microscopy, thermogravimetry, and IR spectroscopy. To optimize the synthesis conditions of M4Na2V10O28 · 10H2O, the ( 1-x)NaVO3 · 2H2O · xMH2AsO4-H2O (0.2 ≤ x ≤ 0.8) isomolar series method was applied to studying the interaction in the NaVO3-MH2AsO4-H2O systems (M = K, Rb, Cs) at the 0.4 mol/L total molar concentration of NaVO3 and MH2AsO4 in solutions. The studied M4Na2V10O28 · 10H2O compounds were shown to be isostructural with triclinic crystals (Z= 1, space group P $ \bar 1 $ \bar 1 ), and their unit cell parameters were estimated.  相似文献   

17.
Syntheses and molecular structures of the heterometallic complexes of nickel cyclopentadienyl triphenylphosphine tellurophenolate with tungsten carbonyls (II and III) (CIF files CCDC nos. 1559733 and 1559734, respectively) are described.  相似文献   

18.
Two new iodobismuthates with the composition LnBiI6?13H2O (Ln = La, Nd) were synthesized and their crystal structures were determined. The compound LaBiI6?13H2O crystalizes in the orthorhombic space group Pna21, a = 24.206(5), b = 8.405(1), c = 26.360(5) Å; the compound NdBiI6?13H2O crystalizes in the monoclinic space group P21/n, a = 14.553(3), b = 13.386(3), c = 27.541(6) Å, β = 92.80(3)°. In both crystal structures, the cations Ln(H2O)93+ and the anions BiI63– alternate, forming a NaCl-type structure, and the structures themselves differ in the arrangement of water of crystallization that leads to the formation of dissimilar systems of hydrogen bonds. Both compounds undergo decomposition when heated, which is accompanied first by a partial liberation of water molecule, followed by pyrohydrolysis to form oxoiodides LnOI as final solid products. According to optical measurements, the band gap of the obtained compounds was equal to 1.78 (La) and 1.71 (Nd) eV.  相似文献   

19.
A new coordination polymer [Cu(H2Tci)2(Bipy)(H2O)] · 2H2O (I) (H3Tci = tris(2-carboxyethyl)isocyanurate, Bipy = 4,4′-bipyridine) has been synthesized and characterized by elemental analysis, IR, and X-ray single-crystal diffraction. The X-ray diffraction analysis reveals that I (C34H42CuN8O21) crystallizes in the monoclinic crystal system, space group P21/c. In I, the metal centers are linked by Bipy ligands to generate an infinite linear chain and the H2Tci ligands adopt monodentate coordination mode to graft the linear chain. The adjacent chains are linked by hydrogen bonds to form a three-dimensional supramolecular framework.  相似文献   

20.
The ligand 4,4′-bipyridyl-N,N′-dioxide (4,4′-dpdo) was used in the synthesis of two complexes, {Co(4,4′-dpdo)2[N(CN)2]2(H2O)2} (1) and {Mn(4,4′-dpdo)2[N(CN)2]2(H2O)2} (2). The complexes were found to be isostructural, triclinic, space group P-1 with Z = 1 and the following unit cell parameters: a = 8.158(8) Å, b = 8.865(8) Å, c = 9.477(9) Å; α = 70.988(13)°, β = 78.778(13)°, γ = 71.964(10)°; V = 612.8(10) Å3 for 1; a = 8.247(14) Å, b = 9.001(16) Å, c = 9.707(17) Å; α = 71.02(2)°, β = 78.63(2)°, γ = 72.62(2)°; V = 646(2) Å3 for 2. Final R-values were 0.075 and 0.083 for 1 and 2, respectively. In the molecules of the complexes, Co(II) or Mn(II) cation is coordinated by two O-atoms of two 4,4′-dpdo ligands, two terminal N-atoms of two dicyanamides, and two O-atoms of water molecules. The crystals are molecular, with adjacent complex molecules linked through a system of O-H...N and O-H...O hydrogen bonds.  相似文献   

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