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1.
The first metal phosphate incorporating isonicotinate ligand, Zn(HINT)(HPO4), was hydrothermally synthesized and characterized by single-crystal X-ray diffraction and solid-state NMR spectroscopy. This compound crystallizes in the monoclinic space group P21/c with cell parameters a=20.5643(8) Å, b=8.5169(4) Å, c=10.3928(4) Å, β=97.466(1)°, and Z=8. The structure consists of 2D neutral sheets of zinc hydrogen phosphate with the dipolar isonicotinate ligand being coordinated to zinc as a pendent group. Adjacent sheets are connected by hydrogen bonding. The 1H magic angle spinning NMR spectrum exhibits three resonances at 15.5, 8.1, and 4.8 ppm with an intensity ratio close to 1:4:1, corresponding to two different types of protons in isonicotinate ligand and one type of protons in hydrogen phosphate groups. The peak at 15.5 ppm can be assigned to the proton bonded to the pyridine nitrogen atom, which confirms the presence of +HNC5H4COO.  相似文献   

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An unusual two-dimensional zinc phosphate with pendant phosphate groups, projecting into the inter-lamellar space between the layers, has been synthesized and is shown to transform into a three-dimensional structure with 16-membered bifurcated channels, giving evidence for the building up process in the formation of open-framework structures.  相似文献   

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Hydro­thermally prepared Ba3V2(HPO4)6 contains a three‐dimensional network of VIIIO6 octahedra [dav(V—O) = 2.014 (2) Å] and HPO4 [dav(P—O) = 1.537 (3) Å] tetrahedra, sharing vertices. 12‐coordinate Ba2+ cations [dav(Ba—O) = 2.944 (4) Å] complete the structure.  相似文献   

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The crystal structure, quadrupole coupling parameters, and the orientation of the electric field gradient tensors for each site of zinc formate dihydrate have been determined. There are two distinct sites in the asymmetric unit: one containing four in-plane waters with two bridging formats, the other containing six bridging formates. The solid-state NMR lineshapes have been assigned to their respective sites by using isotopic labeling and cross-polarization methods. The hydrated site corresponds to the lineshape having a quadrupole coupling constant (Cq) of 9.6 MHz and the anhydrous site has a Cq of 6.2 MHz. The absence of chemical shielding contributions to the observed lineshapes has been verified with a high-field solid-state NMR experiment performed at 18.8 T.  相似文献   

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A new layered compound, K4Mn3(HPO4)4(H2PO4)2 (1), has been synthesized under hydrothermal conditions. It crystallizes in the monoclinic space group P21/n with a = 8.874(2) Å, b = 6.554(1) Å, c = 18.075(4) Å, and β = 93.39(3)°. The structure consists of zigzag [Mn3O14]n chains of edge-sharing MnO6 octahedrons and MnO7 pentagonal bi-pyramids, which form layers of formula [Mn3(HPO4)4(H2PO4)2]4? in the ab plane via H2PO4 and HPO4 units with vertex-sharing. Potassium ions lie between these layers. Magnetic measurements indicate Curie–Weiss behavior above 6 K for 1. A Heisenberg model, with alternating exchange interactions J1J1J2… within the chain and exchange interactions J3J3… between the chains, is proposed to describe the magnetic behavior.  相似文献   

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Scientific-Research Institute of Chemical Reagents and High Purity Chemical Compounds. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 3, pp. 150–153, May–June, 1990.  相似文献   

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以有机分子乙二胺作为模板剂合成了新型磷酸钒孔道化合物(H3NCH2CH2NH3)3^-[(VO)4(PO4)2(HPO4)4,并通过X射线单晶衍射实验进行了结构表征,晶体学数据为:C2/c,a=1.8505(9)nm,b=0.7089(4)nm,c=2.3304(10)nm,β=96.43(3)°,V-3.038(3)nm^3,Z=8,R=0.067,Rw^b=0.1635,该化合物具有非常独特和规整的二维孔道骨架结构,进一步的晶体化学研究表明该化合物为一新的VPO物相。  相似文献   

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An organic–inorganic hybrid compound, poly­[bis­[(pyridine‐4‐carboxyl­ato)­zinc(II)]‐di‐μ3‐phosphato], [Zn2(C6H5NO2)2(HPO4)2], has been hydro­thermally synthesized and structurally characterized. The crystal structure consists of two types of two‐dimensional layers of zinc hydrogenphosphate templated by protonated isonicotinate (ina) (or 4‐pyridine­carboxylic acid), which contain two crystallographically independent centrosymmetric [Zn2(ina)2(HPO4)2] dimers as basic building units. The layers are interconnected via hydrogen‐bonding and heterocyclic ring interactions.  相似文献   

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A single K(2)HPO(4) droplet with size of ~50 μm on a Teflon substrate was forced to enter into the supersaturated state by decreasing the relative humidity (RH), allowing accurate control over the concentration of the solute within a droplet of a nanogram. The K(2)HPO(4) solutions from dilute (0.1-1.0 mol·L(-1) bulk) to concentrated state (a droplet from RH 98.2% to 25.1%) were studied through micro-Raman spectroscopy in the spectral region of about 200-4000 cm(-1). The area ratio between the water stretching band to the sum of the ν(1)-PO(3), ν(2)-POH, and ν(4)-PO(3) bands of the HPO(4)(2-) at various RHs was used to describe the dehydration behavior of a microsized single K(2)HPO(4) droplet in dehumidifying process. The peak position of the v(1)-PO(3) band for the 1 mol·L(-1) bulk solution appeared at 991 cm(-1) and moved to 986 cm(-1) at 98.2% RH, to 978 cm(-1) at 70.2% RH, and then to 964 cm(-1) at 30.0% RH for a droplet, accompanying an increase of the full width at half-height (fwhh) of this peak from 16.3 to 17.2, 22.2, and then to 24.2 cm(-1), indicating transition of the HPO(4)(2-) anions from monomers to dimers/trimers/oligomers and then to polyanions with chain structures in the K(2)HPO(4) solutions. After 25.1% RH, the solid was proved to be K(2)HPO(4)·3H(2)O according to the Raman spectral features. Furthermore, the O-H stretching envelope of a K(2)HPO(4) droplet showed that the intensity ratios of the strong hydrogen bonding component (3255 cm(-1)) to the weak one (3417 cm(-1)) and the cage-like water (2925 cm(-1)) to the weak one (3417 cm(-1)) were sensitive to the HPO(4)(2-) association structures, which can be used to understand the effects of dimers/trimers/oligomers and chain structures of the HPO(4)(2-) associations on the hydrogen bonding of water molecules.  相似文献   

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The two‐dimensional zinc phosphate [H3N(CH2)3NH3]0.5[Zn2(PO4)(HPO4)], has been synthesized hydrothermally using 1,3‐diaminopropane as the template. Its structure contains an inorganic framework with three‐, four‐, or six‐membered rings, built from PO4, PO3(OH) and ZnO4 tetrahedral moieties sharing vertexes. The protonated 1,3‐diaminopropane molecules interact with the framework through hydrogen bonds. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

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《Solid State Sciences》2007,9(2):149-154
The mild-condition syntheses, single-crystal structures and properties of H3N(CH2)5NH3·Zn3(HPO3)4 and β-H3N(CH2)6NH3·Zn3(HPO3)4 are reported. Both are constructed from (3,4)-nets of ZnO4 tetrahedra and HPO3 pyramids, sharing vertices to result in three-dimensional anionic open-frameworks. In both materials, the organic species interacts with the framework by way of N–H⋯O bonds. Crystal data: H3N(CH2)5NH3·Zn3(HPO3)4, Mr = 620.22, orthorhombic, Pccn (No. 56), a = 9.5364 (9) Å, b = 21.8015 (19) Å, c = 9.1118 (7) Å, V = 1894.4 (3) Å3, Z = 4, R(F) = 0.044, wR(F2) = 0.111. β-H3N(CH2)6NH3·Zn3(HPO3)4, Mr = 634.25, monoclinic, P21/n (No. 14), a = 8.7627 (1) Å, b = 13.8117 (2) Å, c = 16.6187 (3) Å, β = 92.680 (1)°, V = 2009.12 (5) Å3, Z = 4, R(F) = 0.072, wR(F2) = 0.187.  相似文献   

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Based on combined DFT/broken symmetry approach, a theoretical analysis of the exchange interactions in the VO(HPO(4)).0.5H(2)O solid is performed. Depending on the crystallographic structures reported in the literature, two very different spin models are formulated. In addition, a complete fit of the temperature-dependent (31)P NMR chemical shift is performed to determine exchange and hyperfine constants. The magnetic models used in the fit are those obtained by our theoretical calculations. The comparison between the calculated and fitted exchange constants confirms the adequacy of an isolated dimer model and rules out the alternating antiferromagnetic chain model for VO(HPO(4)).0.5H(2)O.  相似文献   

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A new layered zinc phosphite with the formula (NH4)[{Zn(H2O)4}0.5Zn2(HPO3)3] has been synthesized under hydrothermal conditions. Its structure was determined by single‐crystal X‐ray diffraction. The compound crystallizes in the triclinic system, space group (No. 2), a = 7.2507(4), b = 9.7982(6), c = 10.2642(6) Å, α = 63.425(2), β = 87.165(2), γ = 72.999(3)°, V = 620.84(6) Å3, Z = 2. The connectivity of ZnO4 tetrahedra, HPO3 pseudo pyramids and ZnO2(H2O)4 octahedra results in macroanionic layers with 4.8 net.  相似文献   

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