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1.
The characteristics of crystal structures of the titanium(IV) diammonium (Ti(NH4)2P4O13) and tin(IV) diammonium (Sn(NH4)2P4O13) tetraphosphates, which are isostructural with similar silicon(IV) and germanium(IV) salts, have been obtained by the Rietveld method using X-ray powder diffraction data. The compounds crystallize in the triclinic system, space group P \(\overline 1 \), Z = 2, a = 15.0291(7) Å, b = 7.9236(4) Å, c = 5.0754(3) Å, α = 99.168(3)°, β = 97.059(3)°, γ = 83.459(3)° for Ti(NH4)2P4O13 and a = 15.1454(7) Å, b = 8.0103(5) Å, c = 5.1053(3) Å, α = 99.898(6)°, β = 96.806(3)°, γ = 83.881(4)° for Sn(NH4)2P4O13. The structure is refined in the isotropic approximation using the pseudo-Voigt function: R p = 0.077, R Bragg = 0.045, R F = 0.057 for Ti(NH4)2P4O13; R p = 0.082, R Bragg = 0.044, R F = 0.046 for Sn(NH4)2P4O13. The hydrogen atoms of the ammonium cations are placed in the calculated positions. A comparative analysis of the structures of the compounds of the MIV(NH4)2P4O13 (MIV = Si, Ge, Ti, Sn) series has been carried out.  相似文献   

2.
The hydrothermal reaction of a mixture of V2O5, VCl3, 2,5-pyridinedicarboxylic acid and diluted H2SO4 for 68 h at 180°C gives a blue colored solution which yields prismatic blue crystals of IV 2 IV O2(SO4)2(H2O)6] (1) in 32% yield (based on V). Complex 1 was investigated by means of elemental analysis (C, H and S), TGA, FT-IR, manganometric titration, Single Crystal X-ray Diffraction Methods and also comparative antimicrobial activities. Crystal data for the compound: monoclinic space group P21/c and unit cell parameters are a = 7.3850(12) Å, b = 7.3990(7) Å, c = 12.229(2) Å, β = 108.976(12)° and Z = 2. Although structure of 1 as a natural mineral has been previously determined, this work covers new preparation method and full characterization of 1 along with comparison of antibacterial activity between 1 and the commercial vanadium(IV) oxide sulfate hydrate compounds, VOSO4 · xH2O (Riedel-de Haën and Alfa Aesar brand names). 1 was evaluated for the antimicrobial activity against gram-positive, gram-negative bacteria, yeasts and mould compared with the commercial VOSO4 · xH2O compounds. 1 showed weak activity against bacteria Bacillus cereus, Nocardia asteroides and yeast Candida albicans. A good antimicrobial activity was recorded against Cirtobacter freundii (15 mm). There are only a few reproducible well-defined vanadium(IV) starting materials to use for exploring the synthesis of new materials. VCl4, VO(acac)2, VOSO4 · xH2O and [V(IV)OSO4(H2O)4] · SO4 · [H2N(C2H4)2NH2] are common starting materials for such applications. In addition to these compounds, 1 can be used as an oxovanadium precursor.  相似文献   

3.
The single crystals of [UO2(C2O4){CONH2N(CH3)2}2] were synthesized and studied by X-ray diffraction. The crystals are monoclinic, a = 7.461(2) Å, b = 8.828(2) Å, c = 11.756(2) Å, β = 107.21(3)°, space group Pc, Z = 2, R = 2.94%. The structure comprises infinite chains [UO2(C2O4){CONH2N(CH3)2}2] extended along [001] and corresponding to the AT11M 2 1 crystallochemical group (A = UO 2 2+ , T11 = C2O 4 2? , M1 = N,N-CONH2N(CH3)2) of uranyl complexes. The chains are connected into a three-dimensional framework by hydrogen bonds involving the oxygen atoms of oxalate and uranyl ions and the N,N-dimethylcarbamide methyl groups.  相似文献   

4.
The subsolidus region of the Ag2MoO4-MgMoO4-Al2(MoO4)3 ternary salt system has been studied by X-ray phase analysis. The formation of new compounds Ag1 ? x Mg1 ? x Al1 + x (MoO4)3 (0 ≤ x ≤ 0.4) and AgMg3Al(MoO4)5 has been determined. The Ag1 ? x Mg1 ? x Al1 + x (MoO4)3 variable-composition phase is related to the NASICON type structure (space group R \(\bar 3\) c). AgMg3Al(MoO4)5 is isostructural to sodium magnesium indium molybdate of the same formula unit and crystallizes in triclinic system (space group P \(\bar 1\), Z = 2) with the following unit cell parameters: a = 9.295(7) Å, b = 17.619(2) Å, c = 6.8570(7) Å, α = 87.420(9)°, β = 101.109(9)°, γ = 91.847(9)°. The compounds Ag1 ? x Mg1 ? x Al1 + x (MoO4)3 and AgMg3Al(MoO4)5 are thermally stable up to 790 and 820°C, respectively.  相似文献   

5.
The heat capacities of Pb2V2O7 and Pb3(VO4)2 as a function of temperature in the range 350–965 K have been studied by the differential scanning calorimetry method. The CP = f(T) curve for Pb2V2O7 is described by the equation Cp = (230.76 ± 0.51) + (73.60 ± 0.50)×10-3T ? (18.38 ± 0.54)×105T-2 in the entire temperature range. For Pb3(VO4)2, there is a well-pronounced extreme point in the CP = f(T) curve at T = 371.5 K, which is caused by the existence of a structural phase transition. The thermodynamic properties of the oxide compounds have been calculated.  相似文献   

6.
The title compound (disodium dipotassium copper(II) tris-[molybdate (VI)]) is prepared by form melt and characterized by single crystal X-ray diffraction and UV-vis spectroscopy. It crystallizes in the triclinic space group P-1 with a = 7.4946(8) Å, b = 9.3428(9) Å, c = 9.3619(9) Å, α = 92.591(7)°, β = 105.247(9)°, γ = 105.496(9)°, V = 604.7 Å3, and Z = 2. Its structure is isotypic with that of Na4Mn(MoO4)3. It is formed by Cu2O10 distorted bi-octahedral dimers linked by two bridging bidentate Mo2O4 tetrahedra and, additionally, two monodentate Mo1O4 tetrahedra to form Cu2Mo4O20 units. These units are linked by the insertion of Mo3O4 tetrahedra to build infinite ribbons disposed along the c axis. All of these ribbons form a one-dimensional framework. Both K1 and K3 cations are located in the inversion center, and all the other atoms are at general positions. The structure model is supported by the bond valence sum (BVS) and charge distribution CHARDI methods. The Cu2+ cations adopt the [4+2] CuO6 Jahn-Teller distortion giving rise to an intense dd transition in the UV-vis absorption spectra.  相似文献   

7.
The saturated vapors of ErCl3 and YbCl3 were studied in a simultaneous electron diffraction and mass spectrometric experiment at 1165 K and 1170 K, respectively. In the vapors of these compounds, we found up to 3 mol.% dimers along with the monomers. The parameters of the r g effective configuration of the monomer molecules were determined. For ErCl3 and YbCl3, the internuclear distances r g(Ln-Cl) were 2.436(5) Å and 2.416(5) Å, and the bond angles ∠g(Cl-Ln-Cl) were 117.0(10)° and 117.2(10)°, respectively. The equilibrium configurations and vibration frequencies of the monomer and dimer molecules were calculated by the HF, B3LYP, and MP2 methods using the combination of the ECPD energy-consistent quasirelativistic core potential, including 4f electrons [Kr4d 104f n ], and the contracted [5s4p3d] valence basis set for Er and Yb atoms and the MIDIX [4s3p1d] basis set for Cl atoms. The parameters of the effective r g configuration of the monomer molecules corresponding to the temperature of the experiment were calculated. The difference between the calculated equilibrium r e(Ln-Cl) and temperature-averaged r g(Ln-Cl) distances was found to be 0.001–0.002 Å and did not exceed the error of the r g(Ln-Cl) parameter determined in the electron diffraction experiment. The experimental parameters of the r g structure were shown to be consistent with the idea about the planar equilibrium geometrical configuration of ErCl3 and YbCl3 molecules.  相似文献   

8.
Attempts of the synthesis in air of complex oxides Sr3RhMnOx and Sr4Rh1.5Mn1.5Ox resulted in revealing formation of a new oxide phase Sr6.3Rh2.35Mn2.35O9 related to quasi-unidimensional family A3n+3m A′ n B3m+n O9m+6n at n = 1 and m = 1. Its structural characteristics and magnetic properties are studied. X-ray data of the obtained phase is indicated on the basis of trigonal cell (spatial group P321) with the parameters: a 9.6239(4) Å; c 1 4.1130(4) Å, c 2 2.4946(2) Å. Manganese and rhodium exist in the compound as the cations Mn4+, Rh3+ and Rh4+, as follows from the data of measuring of magnetic susceptibility in the range 2–300 K.  相似文献   

9.
A continuous solid solution LaMn1?y Cr y O3 with an orthorhombic structure is found to exist in the range of 0.0 ≤ y ≤ 1.0. An orthorhombic solid solution La1?x Sr x CrO3 exists in the range of 0.0 ≤ x ≤ 0.1. The stability boundaries are determined for the perovskite phase La1?x Sr x Mn1?y Cr y O3. An isobaric-isothermal section LaMnO3-SrMnO3-SrCrO4-LaCrO3 of the system La2O3-SrO-Mn3O4-Cr2O3 in air at 1100°C is designed.  相似文献   

10.
Powder and single crystal X-ray diffraction studies have been performed for anhydrous nitrate complexes Rb2[Pd(NO3)4] (I) and Cs2[Pd(NO3)4] (II). Crystal data for I: a = 7.843(1) Å, b = 7.970(1) Å, c = 9.725(1) Å; β = 100.39(1)°, V = 597.9(1) Å 3, space group P21/c, Z = 2, d calc = 2.918 g/cm3; for II: a = 10.309(2) Å, b = 10.426(2) Å, c = 11.839(2) Å; β = 108.17(3)°, V = 1209.0(4) Å3, space group P21/c, Z = 4, d calc = 3.408 g/cm3. The structures are formed by isolated [Pd(NO3)4]2? complex anions and alkali metal cations. The plane-square environment of the Pd atom is formed from the oxygen atoms of the monodentate nitrate groups. The geometrical characteristics of the complex anions are analyzed. Compound II has a short contact Pd...Cs 3.252 Å.  相似文献   

11.
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 \({\bar 4}\)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   

12.
Crystals of double polyphosphates EuCs5(PO3)8 (I) and GdCs5(PO3)8 (II) have been studied by X-ray diffraction. The isostructural crystals of I and II are monoclinic, space group C2. Only unit cell parameters have been determined for the crystals of double Pr and Cs polyphosphate (III). This crystal is isostructural with earlier studied La3Cs15P24O72 · 6H2O (IV). The crystals of compounds III and IV are triclinic, space group P1, Z = 1; a = 11.987(2) and 12.178(5) Å, b = 14.754(8) and 14.740(8) Å, c = 14.692(8) and 14.847(9) Å, α = 60.15(4)° and 60.87(5)°, β = 67.04(4)° and 66.35(4)°, γ = 78.76(3)° and 77.54(4)°, respectively. In compounds I and II, the polyphosphate anions exist as infinite chains. The MIIIO8 polyhedra are isolated from each other but share edges and faces with the CsO n polyhedra.  相似文献   

13.
The syntheses and crystal structures of the layered coordination polymers M(C8H8NO2)2 [M = Mn (1), Co (2), Ni (3) and Zn (4)] are described. These isostructural compounds contain centrosymmetric trans-MN2O4 octahedra as parts of infinite sheets; the ligand bonds to three adjacent metal ions in μ3-N,O,O′ mode from both its carboxylate O atoms and its amine N atom. In each case, weak intra-sheet N–H?O and C–H?O hydrogen bonds may help to consolidate the structure. Crystal data: 1, C16H16MnN2O4, M r = 355.25, monoclinic, P21/c (No. 14), a = 10.6534(2) Å, b = 4.3990(1) Å, c = 15.5733(5) Å, β = 95.1827(10)°, V = 726.85(3) Å3, Z = 2, R(F) = 0.026, wR(F 2) = 0.067. 2, C16H16CoN2O4, M r = 359.24, monoclinic, P21/c (No. 14), a = 10.6131(10) Å, b = 4.3374(4) Å, c = 15.3556(17) Å, β = 95.473(4)°, V = 703.65(12) Å3, Z = 2, R(F) = 0.041, wR(F 2) = 0.091. 3, C16H16N2NiO4, M r = 359.02, monoclinic, P21/c (No. 14), a = 10.6374(4) Å, b = 4.2964(2) Å, c = 15.2827(8) Å, β = 95.9744(14)°, V = 694.66(6) Å3, Z = 2, R(F) = 0.028, wR(F 2) = 0.070. 4, C16H16N2O4Zn, M r = 365.68, monoclinic, P21/c (No. 14), a = 10.6385(5) Å, b = 4.2967(3) Å, c = 15.2844(8) Å, β = 95.941(3)°, V = 694.89(7) Å3, Z = 2, R(F) = 0.038, wR(F 2) = 0.107.  相似文献   

14.
The new compound Sr4B14O25 (4SrO · 7B2O3) corresponding to an oxide ratio of 4: 7 has been identified and synthesized in the SrO-B2O3 system. The crystal structure of the compound has been determined (space group Cmc21, a = 7.734(5) Å, b = 16.332(5) Å, c = 14.556(5) Å, Z = 4, 702 F(hkl), R = 0.078). The borate anions form a three-dimensional framework consisting of borate groups of two types: three-ring structures (2□, Δ) and BO3 triangles. Layers formed by 14-membered rings composed of boron-oxygen tetrahedra and triangles packed within the layer according to the herringbone pattern can be distinguished in the framework. The strontium atoms are located on the mirror symmetry planes between these layers. The compound is metastable and decomposes, on long-term storage, into strontium di- and metaborate.  相似文献   

15.
Phase formation in the BaB2O4-NaBO2-MBO3 (M = Sc, La, Y) system was studied using solid-phase synthesis, visual polythermal analysis, and spontaneous crystallization. This system was shown to be suitable for growing LaBO3. A new compound, ScBaNa(BO3)2, was obtained (trigonal crystal system; space group R \(\bar 3\) unit cell parameters: a = 5.239(1) Å, c = 34.591(1) Å, and V = 822.38(4) Å3).  相似文献   

16.
Compounds described as V2O3(XO4)2, where X = S or Se, were prepared from vanadium(V) oxide mixtures with concentrated sulfuric and selenic acids. The physicochemical properties of the products were studied; for V2O3(SeO4)2, the crystal structure was determined by powder X-ray diffraction and neutron diffraction, and its key differences from the structure of V2O3(SO4)2 were identified. V2O3(SeO4)2 crystallizes in the monoclinic system with the unit cell parameters a = 15.3831(2)Å, b = 5.54096(5)Å, c = 9.71644(7)Å, β = 111.886(1)°, V = 768.51Å3, space group C2/c (no. 15).  相似文献   

17.
Perovskite-like nonstoichiometric oxide La x Cu3V4O12 (space group Im \(\bar 3\), Z = 2, a = 7.313–7.354 Å) with cation-site vacancies has been prepared for the first time at high pressures (p = 6.0–8.0 GPa) and high temperatures (T = 700–1100°C). The compound has metal-type conductivity and paramagnetic properties, and undergoes a phase transition.  相似文献   

18.
A series of complexes [Co(NH3)6] x [ML6(4)] y , where M is Fe(III) and Fe(II), Cr(III), Cu(II); L is CN?, NCS?, 1/2C2O 4 2? , are synthesized. Their IR spectra and thermal decomposition in air are studied, and interplanar distances in crystalline lattices of the complexes are determined. The compounds can be used as precursors for producing homogeneous bimetallic nanodimensional powders.  相似文献   

19.
The crystal structures of compounds from the series [M(NH3)5Cl](NO3)2, (M = Ir, Rh, Ru) were described. The compounds crystallized in the tetragonal crystal system, space group I4, Z = 2. Crystal data for [Ir(NH3)5Cl](NO3)2 (I): a = 7.6061(1) Å, b = 7.6061(1) Å, c = 10.4039(2) Å, V = 601.894(16) Å3, ρcalc = 2.410 g/cm3, R = 0.0087; [Rh(NH3)5Cl](NO3)2 (II): a = 7.5858(5) Å, b = 7.5858(5) Å, c = 10.41357(7) Å, V = 599.24(7) Å3, ρcalc = 1.926 g/cm3, R = 0.0255; [Ru(NH3)5Cl](NO3)2 (III): a = 7.5811(6) Å, b = 7.5811(6) Å, c = 10.5352(14) Å, V = 605.49(11) Å3, ρcalc = 1.896 g/cm3, R = 0.0266. The compounds were defined by IR spectroscopy and XRPA and thermal analyses.  相似文献   

20.
Perovskite-related oxide Tm x Cu3V4O12 (space group Im \(\bar 3\), Z = 2, a = 7.262?7.273 Å) with vacancies in the cationic sublattice has been prepared for the first time under barothermal conditions (p = 7.0?9.0 GPa, T = 900?1100°C). Electric resistivity (10–300 K) and magnetic susceptibility (0–300 K) were studied as a function of temperature. Tm x Cu3V4O12 is shown to have a metallic conductivity and paramagnetism.  相似文献   

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