首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The bismuth basic nitrate [Bi6O4(OH)4](NO3)6 crystallizes in a rhombohedral hexagonal unit cell with parameters , , , Z=6, space group R-3. The synthesis, formula determination, thermogravimetric analysis and nitrate assay, and finally, its crystal structure refinement determined at 150(2) K by synchrotron X-ray microcrystal diffraction are reported. Its structure is built from [Bi6O4(OH)4]6+ polycations, six per unit cell, disordered over two positions. Two oxygen atoms are common to the two antagonist polycations (full occupancy) while the remaining six are partially occupied. The [Bi6O4(OH)4]6+ hexanuclear clusters form columns along the c-axis. The cohesion between polycationic entities is effected by nitrate anions through either OH-ONO2 hydrogen bonds or Bi-ONO2 bonds. One of the two independent [NO3] groups is also disordered over two positions. Only a local order in the columns is obtained by formation of pairs of ordered [Bi6O4(OH)4]6+ polycations.  相似文献   

2.
We report here the first observation of a bismuth potassium nitrate Bi1.7K0.9O2(NO3)2, obtained via thermal decomposition of bismuth and potassium nitrate mixtures. The new compound is orthorhombic, space group Immm (71), Z = 2, with a = 3.8698(7) Å, b = 3.8703(7) Å, and c = 24.1271(4) Å. Its crystal structure was refined from powder X-ray diffraction data by analogy with the mineral beyerite, Bi2O2Ca(CO3)2. The morphology and elemental composition of Bi1.7K0.9O2(NO3)2 were characterized using scanning electron microscopy (SEM) with energy dispersive X-Ray spectroscopy (EDS). Its phase transformations upon heating and products of its thermal decomposition were studied using XRD, TGA and FTIR. At 440 °C, Bi1.7K0.9O2(NO3)2 transforms to another basic bismuth potassium nitrate with demonstrates a very similar XRD pattern but slightly larger cell parameters. At 520 °C, the intermediate oxide nitrate decomposes into a mixture of crystalline α-Bi2O3 and KNO3. The as prepared Bi1.7K0.9O2(NO3)2 showed lower than TiO2 (Degussa P25) photocatalytic activity upon decomposition of a widely used model pollutant, Rhodamine B (RhB) and photooxidation of potassium iodide under UV-vis light irradiation. Interaction with potassium iodide in alkaline media resulted in formation of Bi5O7I.  相似文献   

3.
The steps associated with the thermal decomposition of Zn5(OH)8(NO3)2·2H2O and ZnOHNO3·H2O are re-examined. Previous reports have suggested that Zn5(OH)8(NO3)2·2H2O decomposes to ZnO via two intermediates, Zn5(OH)8(NO3)2 and Zn3(OH)4(NO3)2 whereas ZnOHNO3·H2O has been reported to decompose to ZnO via a Zn3(OH)4(NO3)2 intermediate. In this study, we demonstrate using TG, mass spectral analysis of evolved gases and in situ variable temperature powder X-ray diffraction analysis that, in fact, in the decomposition of Zn5(OH)8(NO3)2·2H2O an anhydrous zinc nitrate intermediate is also involved. We, additionally, show that the decomposition of ZnOHNO3·H2O to ZnO also involves the formation of an anhydrous zinc nitrate intermediate. The anhydrous zinc nitrate formed in both cases is poorly crystallised and this observation may explain why this phase could not be observed by PXRD analysis in the previous studies.  相似文献   

4.
A novel lithium copper vanadate LiCu2VO4(OH)2 (I) and Volborthite Cu3V2O7(OH)2 are two phases obtained at 170 °C by hydrothermal synthesis during the study of the CuO; V2O5; Li2O; H2O system. Compound (I) crystallizes in the orthorhombic system, with the space group P212121 (No. 19) and with the unit-cell parameters a=9.6086(2) Å, b=8.4482(2) Å, c=5.8938(1) Å. The structure was determined from powder by an “ab initio” method using the EXPO software and refined with GSAS, a Rietveld refinement package. Wave-like layers of rutile-type copper chains sharing vertex with the neighbor chains, are linked into a three-dimensional framework by rows of alternating tetrahedra of vanadium and trigonal bipyramids of lithium which share edges and vertices with the copper octahedra.  相似文献   

5.
A new compound, SrBi2B4O10, has been grown by cooling a melt with the stoichiometric composition. It is triclinic, P−1, a=6.819(1), b=6.856(1), c=9.812(2) Å, α=96.09(1), β=109.11(1), γ=101.94(1)°, V=416.5(1) Å3, Z=2. The crystal structure of the compound has been solved by direct methods and refined to R1=0.050 (wR2=0.128). The structure contains Bi-O pseudolayers build up from Bi-O chains involving oxocentred OBi3 triangles. Sr atoms and [B4O9]6− isolated anions (4B:3Δ□:<2Δ□>Δ) are located between the Bi-O packages.The thermal treatment as well as DSC experiment showed that the compound melts above 800 °C presumably according to the peritectic reaction: SrBi2B4O10 ↔ SrB2O4+SrB4O7+ Liquid. According to high-temperature X-ray powder diffraction study thermal expansion of SrBi2B4O10 structure is anisotropic (α11=13, α22=9, α33=2, αV=24×10−6 °C−1).  相似文献   

6.
通过三核铁盐[Fe3O(O2CCH3)6(H2O)3]C1在吡啶溶液中水解聚合得到铁氧簇合物[Fe11O6(OH)6(O2CCH3)15](C5H5N)6。晶体结构表明11个铁离子(Ⅲ)中6个位于扭曲的三棱柱的顶点上,其余5个分别位于三棱柱的每个面之外。铁离子(Ⅲ)之间以氧桥或者羟基氧桥相连。变温磁化率证实铁离子(Ⅲ)之间是反铁磁耦合的。  相似文献   

7.
Two single crystals[Ln(TBPO)4(NO3)2]NTf2 (Ln=Eu, Gd) were prepared and characterized by element analysis, single crystal X-ray diffraction, PXRD, FT-IR, TGA and fluorescence spectroscopy. The two compounds have similar coordinate structures, in which the central metal ion is coordinated by four TBPO (Tri-n-butylphosphine oxide) molecules and two bidentate nitrates, while NTf2-(bis(trifluor-(bis(trifluoromethylsulfonyl) imide anion) acts as the counter anion. The packing modes of the two crystals are same. The two single crystals are the focus on 8-coordinate tetra-TRPO complexes (TRPO is Trialkyphosphine oxides).  相似文献   

8.
合成了离子对配合物(NO2Q1)2[Ni(mnt)2],并用元素分析和红外光谱进行了表征.单晶结构分析结果表明三斜晶系,空间群p-1.晶胞参数a=8.2240(16)A,6=10.777(2)A,c=12.137(2)A,α=72.58(3).,β=72.82(3)°,γ=68.78(3)°,V=935.4(3)A3,Z=1.(NO2Ql)+和[Ni(mnt)2]2-分别形成了完全分立的柱状堆积结构.在阴离子堆积柱内,Ni(Ⅱ)离子形成了一维均匀链.阳离子间,比邻的芳环间存在弱的π…π作用.  相似文献   

9.
A novel heteropoly compound, containing two kinds of coordinated cations, [K(H2O)2Ni(H2O)6]2[V10O28], has been synthesized through routine process and characterized by elemental analyses, IR, 51V NMR and single crystal X-ray diffraction. It crystallizes in the triclinic system, space group P1 with a=0.87382(17) nm, b=1.075 4(2) nm, c=1.111 1(2) nm, α=65.10(3)°, β=75.01(3)°, γ=70.63(3)°, V=0.884 8(3) nm3 and Z=1. The X-ray analysis reveals that the two kinds of coordinated cations are linked by three shared coordinated water molecules, and K+ cations coordinate with ten oxygen atoms: five of which come from V10O286- anion, the other five from water molecules. The title compound exhibits extended 2D array building up of V10O286- groups connected by ten-coordinated K+ cations. The hexahydrated nickel cations Ni(H2O)62+ lie in neat apposition to three adjacent V10O286- clusters. CSD: 413271.  相似文献   

10.
The title compound was synthesized by reaction of Cu(ClO4)2, picolinic acid and carbamide in C2H5OH/CH3CN solution, and characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=14.0481(8), b=9.0130(5), c=18.626(1)?, V=2358.3(2)?3Z=4, Dx=1.771g·cm-3, μ=1.235mm-1 and F(000)=1276. The final R factor is 0.0440 for 1434 observed reflections. The X-ray analysis revealed that the copper(Ⅱ) atom is coordinated by two picolinic ligands in the equatorial plane, while the two oxygen atoms of perchlorate occupy the axial positions of octahedron with lengthened Cu-O distances, resulting in a 4+2 elongated octahedral environment. In the compound, there also exist two protonated carbamide cations for charge balance. CCDC: 195354.  相似文献   

11.
A new sodium gallophosphate, NaGa2(OH)(PO4)2, has been obtained by hydrothermal synthesis under autogeneous pressure at 473 K. It crystallizes in the P21/n space group with the cell parameters a=8.9675(8) Å, b=8.9732(5) Å, c=9.2855(7) Å, β=114.812(6)°, V=678.2 Å3 (Z=4). In its original three-dimensional framework, monophosphate groups share their apices with [Ga4O16(OH)2] tetrameric units, which are built from two GaO5(OH) octahedra and two GaO4(OH) trigonal bipyramids. The sodium cations are located in tunnels running along a, whereas the tunnels running along b are empty.  相似文献   

12.
A new 1,6-hexyldiamine heptaborate, [H3N(CH2)6NH3][B7O10(OH)3] (1), has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis, and thermogravimetric analysis. Compound 1 crystallizes in monoclinic system, space group P21/n with a=8.042(2) Å, b=20.004(4) Å, c=10.103(2) Å, and β=90.42(3)°. The anionic [B7O10(OH)3]n2n layers are interlinked via hydrogen bonding to form a 3D supramolecular network containing large channels, in which the templated [H3N(CH2)6NH3]2+ cations are located.  相似文献   

13.
Preparation and crystal structure of the novel compound [Bi3I(C4H8O3H2)2(C4H8O3H)5]2Bi8I30 are reported. The title compound is prepared by heating of BiI3 and diethylene glycol at 413 K in a sealed quartz glass tube filled with argon. Deep red single crystals are grown and applied to perform X-ray powder diffraction and X-ray single-crystal diffraction measurements. The compound crystallizes triclinic with space group P-1: Z=2, a=13.217(1) Å, b=15.277(1) Å, c=22.498(1) Å, α=84.33(1), β=73.18(1), γ=67.48(1). [Bi3I(C4H8O3H2)2(C4H8O3H)5]2Bi8I30 comprises the novel polynuclear [Bi8I30]6− anion and [Bi3I(C4H8O3H2)2(C4H8O3H)5]3+ as the cation. Cation as well as the anion can be assumed to represent intermediates between solid BiI3 and BiI3 completely dissolved in diethylene glycol.  相似文献   

14.
Single crystals of the [PdL2(NO2)2] complex were obtained for the first time, where L is di-n-butylsulfide. Single crystal and powder diffraction studies provided new data on the molecular and crystal structure of this compound.  相似文献   

15.
Thermogravimetric studies are reported for analytical precipitates of the types MPb[Co(NO2)6] and M2Pb[Co(NO2)6], where M represents the univalent cations NH+4, K+, Rb+, Cs+, and Tl+. Compounds of the latter series are consitently more stable to higher temperatures. For either series increasing the radius of M increases thermal stability. Decomposition to temperatures approaching 500°C involves some four separate processes.  相似文献   

16.
Under mild hydrothermal conditions UO2(NO3)2·6H2O, Hg2(NO3)2·2H2O, and Na2HAsO4·7H2O react to form [Hg5O2(OH)4][(UO2)2(AsO4)2] (HgUAs-1). Single crystal X-ray diffraction experiments reveal that HgUAs-1 possesses a pseudo-layered structure consisting of two types of layers: and . The layers are complex, and contain three crystallographically unique Hg centers. The coordination environments and bond-valence sum calculations indicate that the Hg centers are divalent. The layers belong to the Johannite topological family. The and layers are linked to each other through μ2-O bridges that include Hg?O=U=O interactions.  相似文献   

17.
18.
A new organically templated pentaborate [C6N4H20]0.5[B5O6(OH)4] (1a) was prepared by reactions of triethylenetetramine (TETA) with excess boric acid in aqueous solution and characterized by elemental analysis, FTIR, TG-DTA, powder X-ray diffraction and photoluminescence spectroscopy. The structure of 1a was determined by a single-crystal X-ray diffraction. It crystallizes in the monoclinic system with space group P2(1)/c, a=9200(3) Å, b=14.121(5) Å, c=10.330(4) Å, β=91.512(4)°, V=1341.4(9) Å3, and Z=4. The luminescent properties of the compound were studied, and a green-blue luminescence occurs with an emission maximum at 507 nm upon excitation at 430 nm. The photoluminescence of 1a can be modified from green-blue to white by means of a simple heat-treatment process. The white-light-emission of sample 1c makes the pentaborate a good candidate for display and lighting applications in the white LED.  相似文献   

19.
A new three-dimensional (3D) lanthanide-aromatic monocarboxylate dimer supramolecular network [La2(DNBA)4(DMF)8][W6O19] (DNBA=3,5-dinitrobenzoate, DMF=dimethylfomamide) was synthesized using hexatungstate anion (W6O192-) as template. The crystal structure of the title compound has been determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a=1.334 54(18) nm, b=1.387 52(19) nm, c=1.426 06(19) nm, α=102.189(2)°, β=101.023(2)°, γ=116.349(2)°, V=2.187 2(5) nm3, Dc=2.364 g·cm-3, Z=1, F(000)=1 453.40. The single crystal structure reveals that two La(Ⅲ) ions are bridged by four 3,5-dinitrobenzoate anions as asymmetrically bridging ligands, leading to dimeric cores, [La2(DNBA)4(DMF)8]2+; [La2(DNBA)4(DMF)8]2+ groups are joined together by π-π stacking interaction between the aromatic groups to form a two-dimensional grid-like network; the 2D supramolecular layers are further extended into 3D supramolecular network with a 1D box-like channels by hydrogen bonding interactions, in which hexatungstate polyanions reside. CCDC: 284694.  相似文献   

20.
The mixed lead nitrate oxalate, Pb2(NO3)2(C2O4).2H2O, has been obtained in a polycrystalline form in the course of a study on precursors of nanocrystalline PZT-type oxides. Its crystal structure has been solved from powder diffraction data collected using a monochromatic radiation from a conventional X-ray source. The symmetry is monoclinic, space group P21/c (No. 14), the cell dimensions are a=10.623(2) Å, b=7.9559(9) Å, c=6.1932(5) Å, β=104.49(1)° and Z=4. The structure consists of a stacking of complex double sheets parallel to (1 0 0), forming layers held together by hydrogen bonds. The sheets result from the condensation of PbO10 polyhedra, in which the oxalate and nitrate groups, as well as water molecules, play a major role. The structure is discussed in terms of Pb---O distances, polyhedra shape and lead coordination, with emphasis on the dimensional polymerisation role of water molecules. The thermal behaviour of this layered compound is carefully described from temperature-dependent powder diffraction and thermogravimetric measurements. The enthalpy, ΔrH=232(3) kJ mol−1, and entropy, ΔrS=532(8) J K−1 mol−1, of the dehydration reaction have been determined. The high value of ΔrH demonstrates that the water molecules are strongly bonded in the structure. The complex decomposition proceeds through the crystallisation and decomposition of Pb(NO3)2(C2O4) into Pb(NO3)2 and PbC2O4, and, finally, various lead oxides.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号