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Prof. Dr. Enrique J. Baran Irma L. Botto 《Monatshefte für Chemie / Chemical Monthly》1977,108(4):781-790
The infrared spectra of the title compounds, as well as that of the structurally related mineral meta-autunite, [Ca(UO2)2(PO4)2·n H2O], are reported and discussed using the available crystallographic data. The results can be considered as representative for the full group of the so-called torbernite-minerals. 相似文献
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Z. G. Aliev S. I. Kondrat'ev L. O. Atovmyan M. L. Khidekel' V. V. Karpov 《Russian Chemical Bulletin》1981,30(3):339-341
Conclusions The authors have synthesized anilinium chloranilate (NH3C6H5)2(C6O4Cl2) (I) and acid ammonium chloranilate dihydrate NH4H5O2(C6O4C12) (II). By x-ray structural analysis they have established their crystal structures. In crystals of NH4H5O2(C6O4Cl2) they find the ion H5O
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with the unusual O-H-O bond length of 2.81 A. The anions of chloranilic acid in crystals (I) and (II) have equal charges but different structures.Translated from IzvestiyaAkademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 487–489, March, 1981. 相似文献
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采用等温溶解法测定了偏钒酸铵(NH4VO3)在NH4H2PO4-H2O和(NH4)3PO4-H2O体系中T = 298.15-328.15 K时的溶解度以及溶液的密度和pH值。结果表明, NH4VO3的溶解度随着(NH4)3PO4或NH4H2PO4溶液浓度的增大,先降低后升高,这是由于同离子效应、化学反应平衡及离子活度的共同作用。比较T = 298.15K时, NH4VO3分别在NH4H2PO4-H2O、(NH4)2HPO4-H2O和(NH4)3PO4-H2O体系中溶解度,发现在相同的磷酸盐浓度下, NH4VO3的溶解度在NH4H2PO4-H2O体系中最大,在(NH4)3PO4-H2O体系中居中,在(NH4)2HPO4-H2O体系中最小。进一步地,在T = 298.15 K和磷酸盐浓度C = 0.5 mol·kg-1时,结合pH值和反应溶度积常数KSP等计算三个体系中的平均离子活度系数(γ±),发现γ±值在(NH4)2HPO4-H2O体系中最大,在(NH4)3PO4-H2O体系中居中,在NH4H2PO4-H2O体系中最小,与溶解度规律一致。 相似文献
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Cis-dioxo-tungsten(Ⅵ) complex, (NH2CH2CH2NH2)[(NH2CH2CH2NH3)2WⅥO2(NHC6H4NH)2]2·H2O is synthesized at room temperature by the reaction of sodium tungstate with o-phenylenediamine. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21/ c, a=0.712 8(2) nm, b=3.081 1(10) nm, c=0.981 9(3) nm, β=102.615(4)°, V=2.104 4(11) nm3, Z=2, μ=55.26 cm-1, F(000)=1 176. Compared the complex with its analogous biomimetic complexes of the cofactor of molybdoenzymes and tungstoenzymses, it is found that the variance of the coordination atoms and the metal ions center have no influence on the coordination feature, and exhibits distored octahedral coordination with cis-dioxo o-phenylenediamine. CCDC: 252834. 相似文献
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The 1/2V2O5-H2C2O4/H3PO4/NH4OH system was investigated using hydrothermal techniques. Four new phases, (NH4)VOPO(4).1.5H2O (1), (NH4)0.5VOPO(4).1.5H2O (2), (NH4)2[VO(H2O)3]2[VO(H2O)][VO(PO4)2]2.3H2O (3), and (NH4)2[VO(HPO4)]2(C2O4).H2O (4), have been prepared and structurally characterized. Compounds 1 and 2 have layered structures closely related to VOPO(4).2H2O and A0.5VOPO4.yH2O (A = mono- or divalent metals), whereas 3 has a 3D open-framework structure. Compound 4 has a layered structure and contains both oxalate and phosphate anions coordinated to vanadium cations. Crystal data: (NH4)VOPO(4).1.5H2O, tetragonal (I), space group I4/mmm (No. 139), a = 6.3160(5) A, c = 13.540(2) A, Z = 4; (NH4)0.5VOPO(4).1.5H2O, monoclinic, space group P2(1)/m (No. 11), a = 6.9669(6) A, b = 17.663(2) A, c = 8.9304(8) A, beta = 105.347(1) degrees, Z = 8; (NH4)2[VO(H2O)3]2[VO(H2O)][VO(PO4)2]2.3H2O, triclinic, space group P1 (No. 2), a = 10.2523(9) A, b = 12.263(1) A, c = 12.362(1) A, alpha = 69.041(2) degrees, beta = 65.653(2) degrees, gamma = 87.789(2) degrees, Z = 2; (NH4)2[VO(HPO4)]2(C2O4).5H2O, monoclinic (C), space group C2/m (No. 12), a = 17.735(2) A, b = 6.4180(6) A, c = 22.839(2) A, beta = 102.017(2) degrees, Z = 6. 相似文献
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M. V. Lomonosov Moscow State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 138–140, September–October, 1990. 相似文献
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《Solid State Sciences》2007,9(7):644-652
Na2Cu(PO2NH)4·7H2O and KxNa2−xCu(PO2NH)4·7H2O (x ≈ 0.5) were synthesized by gel crystallization in sodium silicate gels. The crystal structures were solved by single-crystal X-ray methods and found to be isotypic (Pnma, Z = 4; Na2Cu(PO2NH)4·7H2O: a = 627.5(2) pm, b = 1456.0(3) pm, c = 1900.5(4) pm, R1 = 0.0352; K0.47Na1.53Cu(PO2NH)4·7H2O: a = 632.2(2) pm, b = 1460.0(3) pm, c = 1936.4(4) pm, R1 = 0.0345). The P4N4 rings of the tetrametaphosphimate anion exhibit a distorted chair-2 conformation with admixtures of saddle and crown conformation. The M+ ions are six- and sevenfold coordinated by oxygen atoms, the Cu2+ ions are fivefold coordinated, respectively. The MO7 and the CuO5 units form pairs of face-sharing polyhedra, which are connected by common corners forming chains and are further interconnected by tetrametaphosphimate anions, forming a three-dimensional network structure with channels along [100] and [010]. The MO6 units form chains of face-sharing polyhedra, which are situated in the channels along [100]. Extended hydrogen bonding reinforces the three-dimensional framework structure of the compounds. 23Na-MAS NMR experiments were conducted to verify the K/Na distribution on the M sites derived from the X-ray crystal structure refinement. 相似文献
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I. A. Teslya A. I. Tursina L. D. Iskhakova L. M. Avdonina V. V. Marugin 《Journal of Structural Chemistry》1990,31(6):956-960
Scientific-Research Institute of Chemical Reagents and Ultrapure Chemical Substances. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 6, pp. 123–127, November–December, 1990 相似文献
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P. V. Klevtsov L. A. Glinskaya R. F. Klevtsova K. S. Aleksandrov 《Journal of Structural Chemistry》1997,38(4):615-619
Single crystals of CsNaMoO4 · 2H2O were synthesized, and the crystal structure of this compound was determined from X- ray diffraction data (SYNTEX P21 automatic diffractometer, MoKα radiation, 2252 reflections, R =0.037). Crystals are orthorhombic, space group P212121 with unit cell dimensions a =6.379(1), b =8.625(1), c =13.671(2) å, Z =4. The structure of the binary molybdate consists of continuous columns of face- sharing Na octahedra with attached MoO4 tetrahedra. The neighboring columns are linked by the Cs cations and the hydrogen bonds of the water molecules entering into the coordination polyhedra of the Na and Cs atoms. 相似文献
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《Journal of fluorine chemistry》1986,31(1):29-35
(NH4)3VOF6 and (NH4)3NbOF6 were prepared by a simple solid state route and their thermolysis studied. It is concluded that both these compounds have water of hydration, their structures are different and they show first order phase transitions. 相似文献
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Conclusions The new molecular compound NH4F·H2O2 was observed during an investigation of the fusibility of the NH4F-H2O2-H2O system and has been isolated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1617–1618, July, 1968. 相似文献
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Single crystals of Li4(PO2NH)4 · 4 H2O were obtained by dissolving LiOH and H4(PO2NH)4 · 2 H2O in water and subsequent precipitation with acetone and ethanol followed by slow evaporation of the solvents. The structure of Li4(PO2NH)4 · 4 H2O was solved by single‐crystal X‐ray methods ( (No. 2), a = 489.2(2), b = 853.2(2), c = 880.5(2) pm, α = 101.71(3), β = 102.39(3), γ = 94.88(3)°, Z = 1). The structure is composed of LiO4 tetrahedra and (PO2NH)44? ions. The P4N4 rings of the anions exhibit a slightly distorted chair–1 conformation, which is supported by IR data and has been described by torsion angles, displacement asymmetry parameters and puckering parameters. Via Li+ ions and hydrogen bonds, the tetrametaphosphimate anions are connected forming a three‐dimensional network. 相似文献
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We have studied the thermodynamic properties of the ammonium nitrate/ammonium sulfate/water system using differential scanning calorimetry and infrared spectroscopy of thin films at low temperatures. This is the first study focused on low temperatures, as previous experimental work on this system has been at 273 K and above. We have combined our experimental results with melting point data from the literature at high temperatures to create a solid/liquid phase diagram of the ammonium nitrate/ammonium sulfate/water system for temperatures below 343 K. Using phase diagram theory and Alkemade lines, we predict which solids are stable at equilibrium for all concentrations within the studied region. We also observed the decomposition of a solid at low temperatures which has not previously been reported. Finally, we have compared our predicted solids and final melting temperatures to the Aerosol Inorganics Model (AIM). 相似文献
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I. L. Botto E. J. Baran A. C. Garcia 《Journal of Thermal Analysis and Calorimetry》1986,31(6):1301-1308
The IR and Raman spectra and the thermal behaviour of the isomorphous compounds (NH4)3Ga(C2O4)3·3H2O and (NH4)3Al(C2O4)3·3H2O were investigated. Detailed stoichiometries, sustained by TG, DTA and IR spectroscopic analyses, were found in both cases. Different results, associated with the different polarizing powers of the metal cations, were obtained. The first evidence was found of the formation of basic gallium carbonates. 相似文献