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1.
NaZr2–xBx(PO4)3–2x(SO4)2x (0 ≤ x ≤ 1.25, B = Mg, Co, Ni, Cu, Zn), and NaZr2–xRx(PO4)3–x(SO4)x (0 ≤ x ≤ 1.25, R = Al, Fe) phosphate-sulfates series have been prepared by a sol–gel process. These compounds belong to the NaZr2(PO4)3 (NZP) structure family and crystallize in hexagonal crystal system, space group R\(\bar 3\)c. Limited solid solution series were found to exist; their formation temperatures and thermal stability limits were determined. Particle sizes as determined by microstructure observation were 50–200 nm, and for Cu- and Zn-containing samples, 200–500 nm. The thermal expansion of phosphate-sulfate NaZr1.25Cu0.75(PO4)1.5(SO4)1.5 was studied in the range 25–700°C. Thermal expansion coefficients and thermal expansion anisotropy were found to be αa =–5.40 × 10–6 °C–1, αс = 18.88 × 10–6 °C–1, αavg = 2.69 × 10–6 °C–1, and Δα = 24.28 × 10–6 °C–1.  相似文献   

2.
Phase formation in the A1 + x Al x Ti2 ? x P3O12 (A = Li, Na, K, Rb, or Cs; 0 ≤ x ≤ 2.0) and B0.5(l + x)Al x Ti2 ? x P3O12 (B = Mg, Ca, Sr, or Ba; 0 ≤ x ≤ 2.0) systems was studied using X-ray powder diffraction, electron probe microanalysis, and IR spectroscopy. The following double and triple orthophosphates were found to exist: A1 + x Al x Ti2 ? x (PO4)3 with A = Li (0 ≤ x ≤ 0.3), Na (0 ≤ x ≤ 1.0), K (x = 0, 1.0, or 2.0), Rb (x = 0, 1.0, or 2.0), or Cs (0 ≤ x ≤ 1.0) and B0.5(l + x)Al x Ti2 ? x (PO4)3 with B = Mg and Ba (x = 0), Ca and Sr (0 ≤ x ≤ 0.2). These orthophosphates crystallize in the structure types of kosnarite, langbeinite, cesium titanium arsenate, potassium aluminum phosphate, or rubidium aluminum phosphate. Their crystal parameters were calculated. For CsTi2(PO4)3 (x = 0), Rietveld refinement was carried out: space group Ia \(\bar 3\) d, Z = 32, a = 19.909(5) Å, V = 7892(1) Å3. This compound has a framework structure. The framework is built of TiO6 octahedra and PO4 tetrahedra; eight- and 12-coordinated Cs+ cations populate interstices.  相似文献   

3.
The temperature dependence of heat capacity C° p = f(T) of crystalline arsenate Mg0.5Zr2(AsO4)3 was studied by precision adiabatic vacuum and differential scanning calorimetry in the temperature range 8?670 K. The standard thermodynamic functions C° p (T), H°(T)–H°(0), S°(T), and G°(T)–H°(0) of the arsenate for the range from Т → 0 to 670 K and the standard formation entropy at Т = 298.15 K were calculated from the obtained experimental data. Based on the low-temperature capacity data (30–50 K) the fractal dimension D of the arsenate was determined, and the topology of its structure was characterized. The results were compared with the thermodynamic data for the structurally related crystalline phosphates M0.5Zr2(PO4)3 (M = Mg, Ca, Sr, Ba, Ni) and arsenate NaZr2(AsO4)3.  相似文献   

4.
The structures of three novel octahedral rhenium cluster compounds [Re6S8(CN)2(py)4]·H2O (1), [Re6S8(CN)2(4-Mepy)4] (2), [Re6S8(CN)2(4-Mepy)4]·4-Mepy (3) (py = pyridine, 4-Mepy = 4-methylpyridine) are determined by X-ray crystallography. Crystal data are: C2/m space group, a = 14.813(1) Å, b = 14.772(1) Å, c = 9.2122(6) Å, β = 119.085(2)°, V = 1761.7(2) Å3, d x = 3.318 g/cm3, R = 0.0585 (1); I41/amd space group, a = 16.0018(3) Å, c = 14.7186(5) Å, V = 3768.81(16) Å3, d x = 3.169 g/cm3, R = 0.0489 (2); P21/c space group, a = 9.0452(4) Å, b = 15.8065(7) Å, c = 15.2951(6) Å, β = 103.700(2)°, V = 2124.57(16) Å3, d x = 2.957 g/cm3, R = 0.0245 (3). Molecular cluster complexes interact via π-π stacking affording 3D frameworks in 1 and 2 and chains in 3.  相似文献   

5.
The crystal structures of compounds of the composition [Rh(H2O)6]2(SO4)3·5H2O (I) and [Rh(H2O)6]PO4 (II) are determined. Crystallographic data for I: a = 7.272(9) Å, b = 27.047(1) Å, c = 12.464(9) Å, β = 97.038(10)°, P21 space group, Z = 4, d x = 2.184 g/cm3; for II: a = 9.746(6)Å, b = 6.877(7) Å, c = 23.623(6) Å, β = 100.601(10)°, C2/c space group, Z = 8, d x = 2.611 g/cm3. Compounds are analyzed by IR spectroscopy and powder XRD. Crystalline phase I is well soluble in water, whereas II is almost insoluble.  相似文献   

6.
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   

7.
Triple phosphates A2FeTi(PO4)3 (A = Na, Rb) were synthesized by the solid-phase method and studied by electronic microscopy, electron probe X-ray microanalysis, and IR and Mössbauer spectroscopy. The crystal structure of the obtained compounds was refined by X-ray powder diffraction (the Rietveld method). The unit-cell parameters are as follows: for Na2FeTi(PO4)3 (space group R \(\overline 3 \) c, Z = 6), a = 8.6015(1) Å, c = 21.718(1) Å, V = 1391.52(1) Å3; for Rb2FeTi(PO4)3 (space group P213, Z = 4), a = 9.8892(2) Å, V = 967.12(1) Å3. The base of the crystal structures is a mixed octahedral-tetrahedral framework {[FeTi(PO4)3]2?}3∞. Na+ and Rb+ cations are arranged in cavities of the framework. The influence of cationic substitutions on the change of the structural type of the isoformular compounds A2FeTi(PO4)3 (A = Na, Rb) was considered.  相似文献   

8.
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   

9.
New compounds Pb4La(GeO4)2(VO4)(I) and Sr5La5(GeO4)5(VO4)O(II) were prepared and identified. Compound I has the structure of apatite, a = 10.108(1) Å, c = 7.369(1) Å, V = 652.1(2) Å3. Compound II has the structure of oxyapatite, a = 9.9028(5) Å, c = 7.3162(4) Å, V = 621.34(6) Å3.  相似文献   

10.
The crystal structure of [Os(NH3)5Cl][ReCl6] has been refined by X-ray powder analysis: a = 11.645(3) Å, b = 8.3788(2) Å, c = 15.277(4) Å, β = 91.029(6)°, V = 1490(1) Å3, d x = 3.163 g/cm3, space group P21/m, Z = 4. The thermolysis product of the salt in a hydrogen atmosphere is a solid substitution solution Os0.5Re0.5: a = 2.753(2) Å, c = 4.366(3) Å, space group P63/mmc; coherent scattering region (CSR) is ~230 Å.  相似文献   

11.
Double complex salts (DCS) [RuNO(NH3)4(H2O)]2[MCl4]Cl4·2H2O, M = Pt (I) and Pd (II), are prepared and characterized using IR spectroscopy, single crystal and powder X-ray diffraction, and thermogravimetric analysis. Crystalline phases of I and II are isostructural (P2(1)/n space group) and have the following crystallographic characteristics: a = 6.689 Å, b = 15.609 Å, c = 12.348 Å, V = 1289.1 Å3, Z = 2, d x = 2.425 g/cm3 (I) and a = 6.637 Å, b = 15.521 Å, c = 12.244 Å, V = 1261.2 Å3, Z = 2, d x = 2.255 g/cm3 (II). The thermolysis of the obtained DCS in the hydrogen atmosphere affords two-phase mixtures of limited solid solutions of the metals: hcp for ruthenium-based ones and fcc for Pt or Pd based solutions. On decomposition in the helium atmosphere the products contain a minor amount of RuO2. For the phases obtained during thermolysis the parameters are determined and the compositions are estimated. The heating of I to 400°C in the helium-air atmosphere yields a nanocrystalline composite Pt+RuO2 with CSR of ~20 nm.  相似文献   

12.
Thermal decomposition of [Pt(NH3)4][ReHlg6] binary complex salts (Hlg = Cl, Br) in a hydrogen atmosphere has been studied. Polycrystal X-ray diffractometry indicated that two-phase metallic systems are the final products of thermolysis. Structure refinement was performed for [Pt(NH3)4][ReCl6] by the combined technique involving decomposition of the diffractogram into individual reflections, isolation of reflections most sensitive to the position of separate light atoms, and full-profile analysis. Crystal data for PtReN4Cl6H12: a = 11.616(1) Å, b = 10.998(1) Å, c = 10.377(1) Å, V = 1148.1 Å3, space group Cmca, Z = 4, d x = 3.831 g/cm3. The indices are Rp = 5.48%, Rwp = 10.01%, R(F2) = 12.62%. The coordination polyhedron of Re is an almost regular octahedron: Re-Cl 2.34–2.36 Å, ∠ Cl-Re-Cl 86.9–90.3°; the coordination polyhedron of Pt is a square: Pt-N 2.04 Å, ∠N-Pt-N 90.4°.  相似文献   

13.
X-ray structural analysis has been performed for two complex compounds: Cu(en)2(o-HB)2H2O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) Å3, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)2(OH2)2]2+(o-AB?)2 (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) Å3, P21/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment.  相似文献   

14.
Vanadium(V) complexes of general composition M3VO2(SO4)2 (M = Rb, Cs) were synthesized by a solid-state route. The individuality of the synthesized compounds was proved by X-ray and neutron diffraction, vibrational spectroscopy, and microscopic analysis. The X-ray diffraction patterns of M3VO2(SO4)2 were indexed to fit the monoclinic system (space group P2/c, Z = 4) with the following unit cell parameters: a = 11.6487(2) Å, b = 8.4469(2) Å, c = 12.1110(2) Å, β = 109.483(1)°, V = 1123.43 Å3 (Rb); a = 12.0546(3) Å b = 8.7706(2) Å, c = 12.6496(3) Å, β = 109.843(2)°, V = 1257.99 Å3 (Cs). In the crystal structure of M3VO2(SO4)2, [VO2(SO4)2]3? complex anions can be discerned in which the vanadium atom is surrounded by five oxygen atoms: two oxygen atoms form short terminal V–O bonds, and three oxygen atoms are from the two sulfato groups, one of which acts as a monodentate ligand and the other acts as a bidentate chelating ligand.  相似文献   

15.
The new phosphate Cs2Mn0.5Zr1.5(PO4)3 was synthesized for the first time and characterized by X-ray diffraction. Its crystal structure was refined in space group P213, Z = 4 at 25°C (a = 10.3163(1) Å, V = 1097.93(1) Å3), by the Rietveld method using the powder X-ray diffraction data. The structure is built of an octahedral-tetrahedral framework {[Mn0.5Zr1.5(PO4)3]2?}3∞ with cesium atoms being located in large cavities. The hydrolytic stability of the powdered phosphate containing 137Cs radionuclide was studied. The minimum achieved 137Cs leaching rate was 4 × 10?8 g/cm2 day.  相似文献   

16.
Novel complex salts [Au(en)2]Cl(ReO4)2 (I) and [Au(en)2](ReO4)3 (II), en = ethylenediamine, are obtained. Their crystal structures are determined by single crystal X-ray diffraction. Complex I crystallizes in the triclinic crystal system: a = 6.2172(7) Å, b = 7.1644(8) Å, c = 8.8829(8) Å, α = 96.605(4)°, β = 110.000(4)°, γ = 97.802(4)°, P-1 space group, Z = 1, d x = 3.905 g/cm3; complex II crystallizes in the monoclinic crystal system: a = 15.244(2) Å, b = 7.6809(8) Å, c = 9.3476(12) Å, β = 127.004(3)°, C2 space group, Z = 4, d x = 4.057 g/cm3.  相似文献   

17.
Indium strontium hydrogen nitrate SrIn2[PO3(OH)]4 was synthesized under mild hydrothermal conditions (T = 180 or 200°C) and characterized using IR spectroscopy, chemical analysis, and thermal analysis. A structure model obtained ab initio was refined by the Rietveld method: a= 9.6412(1) Å, b = 13.763(1) Å, c = 9.3579(1) Å, R obs = 0.0183, R p = 0.0493 (space group B2212, Z = 4). The acentricity of the structure was confirmed by SHG tests (I /I 2ω(SiO2) ≈ 2.0). In the SrIn2[PO3(OH)]4 structure, indium atoms reside in distorted InO6 octahedra and form, together with PO3(OH) tetrahedra, a mixed 3D structure {In2[PO3(OH)]4} 3∞ 2? whose voids are occupied by Sr2+ cations (CN = 8). The block-dimer In2(HPO4)10 is the most informative unit of the framework. Blocks are condensed into infinite columns running in the [101] direction. The compound is thermally stable up to 400°C.  相似文献   

18.
The crystal structure of dichlorobis(dimethylsulfoxide-O)copper(II), [CuCl2(DMSO)2] (I), previously determined by Willett and Chang, is reinvestigated. It crystallizes in the orthorhombic system with the space group Pnma (N°62), Z = 4, and unit cell parameters a = 8.053(1) Å, b = 11.642(5) Å, c = 11.347(3) Å. Our structure determination is of a significantly higher precision in terms of bond lengths, angles, and R factors (e.g., Cu1–O1 = 1.9737(24) Å, O1–Cu1–O1i = 173.08(13)° (symmetry code: I x, 1/2–y, z) and R(F 2) = 0.046 compared to 1.955(4) Å, 173.0(3)° and R(F) = 0.075). In contrast to the previous investigation, all H atoms are placed at calculated positions. In the title molecule, the CuII atom is five coordinated in a distorted square pyramidal geometry. Thus, as reported previously, it can be shown that the crystal structure consists of [CuCl2(DMSO)2] molecules which, by virtue of long Cu–Cl interactions, are tied together to form chains parallel to the [100] direction. The density functional theory (DFT) optimized structure at the B3LYP/6-311++G(2d,2p) level is compared with the experimentally determined molecular structure. The HOMO-LUMO energy gap and other related molecular properties are also calculated. Comprehensive experimental and theoretical structural studies on the studied complex are carried out by FT-IR and UV-visible spectroscopies.  相似文献   

19.
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   

20.
Tetramminenickel hydrogen hexamolybdoaluminate and hexamolybdogallate(III) of compositions [Ni(NH3)4] · H[AlMo6O18(OH)6] · 10H2O (I) and [Ni(NH3)4] · H[GaMo6O18(OH)6] · 10H2O (II) were synthesized and characterized by mass spectrometry, thermogravimetry, X-ray powder diffraction, and IR spectroscopy. Their crystals are triclinic. For compound I, a= 17.30 Å, b= 14.69 Å, c= 10.45 Å, α = 129.07, β = 65.91°, γ = 138.01°, V = 1338.7l Å3, ρcalcd = 2.75g/cm3, Z = 2; for compound II, a = 17.38 Å, b= 14.75 Å, c= 10.51 Å, α = 131.38°, β= 65.96°, γ = 138.09, V = 1338.15 Å3, ρcalcd = 2.68 g/cm3, Z = 2.  相似文献   

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