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1.
A hydrothermal reaction of a mixture of cobalt (II) oxalate, phosphorous acid, piperazine and water at 150 °C for 96 h followed by heating at 180 °C for 24 h gave rise to a new inorganic-organic hybrid solid, [C4N2H12][Co4(HPO3)2(C2O4)3], I. The structure consists of edge-shared CoO6 octahedra forming a [Co2O10] dimers that are connected by HPO3 and C2O4 units forming a three-dimensional structure with one-dimensional channels. The amine molecules are positioned within these channels. The oxalate units have a dual role of connecting within the plane of the layer as well as out of the plane. Magnetic susceptibility measurement shows the compound orders antiferromagnetically at low temperature (). Crystal data: I, monoclinic, space group=P21/c (No. 14). a=7.614(15), b=7.514(14), , β=97.351(3)°, , Z=2, , , R1=0.0310 and wR2=0.0807 data [I>2σ(I)].  相似文献   

2.
A new vanadium(III) phosphite, (C4H8N2H4)0.5(C4H8N2H3)[V4(HPO3)7(H2O)3]1.5H2O, has been synthesized hydrothermally by using V2O5, H3PO3 as reactants, piperazine as the structure-directing agent. The as-synthesized product was characterized by powder X-ray diffraction, IR spectroscopy, inductively coupled plasma analysis, thermogravimetric analysis, and SQUID magnetometer. Single-crystal X-ray diffraction analysis shows that the title compound crystallized in the trigonal space group (No. 165) with the parameters: , , and Z=4. Its structure is built up by alternation of octahedral VO6 or VO5(H2O) and pseudo-pyramidal HPO3 units to form infinite 2D layers, and these layers are interconnected by sharing vertex-oxygen with octahedral VO6 units to generate a 3D open-framework structure with 12-membered ring channels in a and b directions, respectively, where there exist entrapped diprotonated and mono-protonated piperazine cations, and water molecules. Magnetic measurement indicates that paramagnetic behavior is observed down to 4 K.  相似文献   

3.
H. Naïli  W. Rekik  T. Bataille  T. Mhiri 《Polyhedron》2006,25(18):3543-3554
A new organically templated metal sulfate has been synthesized and characterized. At room temperature, dabcodiium hexaaquacopper(II) bis(sulfate), (C6H14N2)[Cu(H2O)6](SO4)2 crystallizes in the monoclinic symmetry (space group P21/n) with the following unit cell parameters: a = 6.9533(2), b = 12.5568(2), c = 9.9434(2) Å; β = 90.526(1)° and Z = 2. Its crystal structure is built from isolated [Cu(H2O)6]2+, and disordered ions linked together by a hydrogen-bonding network. The title compound undergoes a reversible phase transition of the first-order type at 265.7/281.8 K on heating–cooling runs. Below the phase transition temperature, the structure is fully ordered.  相似文献   

4.
A new dabcodiium-templated nickel sulphate, (C6H14N2)[Ni(H2O)6](SO4)2, has been synthesised and characterised by single-crystal X-ray diffraction at 20 and −173 °C, differential scanning calorimetry (DSC), thermogravimetry (TG) and temperature-dependent X-ray powder diffraction (TDXD). The high temperature phase crystallises in the monoclinic space group P21/n with the unit-cell parameters: a = 7.0000(1), b = 12.3342(2), c = 9.9940(2) Å; β = 90.661(1)°, V = 862.82(3) Å3 and Z = 2. The low temperature phase crystallises in the monoclinic space group P21/a with the unit-cell parameters: a = 12.0216(1), b = 12.3559(1), c = 12.2193(1) Å; β = 109.989(1)°, V = 1705.69(2) Å3 and Z = 4. The crystal structure of the HT-phase consists of Ni2+ cations octahedrally coordinated by six water molecules, sulphate tetrahedra and disordered dabcodiium cations linked together by hydrogen bonds. It undergoes a reversible phase transition (PT) of the second order at −53.7/−54.6 °C on heating-cooling runs. Below the PT temperature, the structure is fully ordered. The thermal decomposition of the precursor proceeds through three stages giving rise to the nickel oxide.  相似文献   

5.
According to X-ray crystal structure analyses “cis-benzenetrisimine” (2) and “cis-benzenetrioxide” (1) act as tridentate ligands in their 2:1- and 4:1-complexes 7 (Co(C6H9N3)2(NO3)3) and 8 (Ba(C6H6O3)4(ClO4)2), resp. The latter is the rare example of an organic complex with the (approximate) T-symmetry.  相似文献   

6.
We have prepared polycrystalline samples of Zn(C3H3N2)2 by a liquid-mix technique. Characterization of the obtained samples has been performed with the aid of elemental, thermogravimetric, infrared spectra and X-ray powder diffraction analysis. We have measured electric permittivity (ε′, ε″), ac-conductivity (σac), magnetic susceptibility (χ) and specific heat (Cp). The obtained data indicate that this material is a new diamagnetic insulator. A maximum around is found in CpT−3, and it is suggested that in addition to the Debye lattice contribution, there exists a low-frequency mode assigned as an Einstein mode contribution to the total specific heat. As a main result of the study, we found ε′ to be constant in a wide temperature range and to have a small value of 2.3 at room temperature. This feature in combination with other properties like crystallization, good thermal stability (up to 400°C), weak moisture sensitivity and simple synthesis makes Zn(C3H3N2)2 to be a promising candidate for good insulating material in various applications.  相似文献   

7.
The thermolysis of the complexes [Co(NH3)6]2C2O4[Cu(C2O4)2]2 (I) and [Co(NH3)6]Cl[Cu(C7H4O3)2] (II) in air and hydrogen at 200, 350, and 500°C and the composition and properties of the thermolysis products are considered. The oxidative thermolysis of the complexes yields mixtures of cobalt and copper oxides, including mixed ones. The reductive thermolysis of the complexes yields a Co + Cu bimetallic powder in the case of compound I and a Co + Cu + C powder in the case of compound II. The thermal behavior of the complexes is governed by the nature of the ligand coordinated to the copper atom. The observed data are explicable in terms of the properties of this ligand. The chemistry of the oxidative and reductive thermolysis is discussed. Original Russian Text ? D.P. Domonov, S.I. Pechenyuk, N.L. Mikhailova, A.T. Belyaevskii, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 7, pp. 1104–1110.  相似文献   

8.
用T-jump/FTIR研究MnCP、NiCP和PbCP的快速热分解(英)   总被引:1,自引:0,他引:1  
0IntroductionCarbohydrazideisahydrazinederivativewithwhitecrystalofstrongreducingbehaviors.Becauseithasmanycoordinationatoms(fournitrogenatomsandoneoxygenatom),carbohydrazidecan,therefore,beusedasmultidentateligand.Itscoordinationcom鄄poundiswidelyusedint…  相似文献   

9.
The rates of the thermal reaction of the nickel(0) complex Ni[P(C2H5)3]4 with the alkyl halides CH3Br, CH3I in toluene have been compared with those of the reactions of the nickel(I) complexes Ni(X)[P(C2H5)3]3 (X  Br,I). The organic products from CH3X are methane and ethane, and those from C2H5I are ethane and ethylene. The reactivity of the nickel(I) complexes is 10–20 times less than that of the nickel(0) complex. The result suggest that the first step of the reaction of nickel(0) with CH3I is the expected oxidative addition of the halide to the metal substrate. The intermediate thus formed decomposes to produce ethane (and small amounts of methane) without further reaction with the organic halide. This mechanism is supported by deuterium-labeling experiments.  相似文献   

10.
11.
Two organically templated zincophosphites, (C6H14N2)·[Zn3(HPO3)4] and (C4H14N2)·[Zn3(HPO3)4] have been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction. (C6H14N2)·[Zn3(HPO3)4] crystallizes in the triclinic space group , with cell parameters, a=9.363(4) Å, b=10.051(4) Å, c=10.051(4) Å, α=85.777(13)°, β=82.091(9)°, and γ=79.783(9)°. (C4H14N2)·[Zn3(HPO3)4] crystallizes in the monoclinic space group P21/c, with cell parameters, a=9.9512(3) Å, b=10.1508(3) Å, c=17.8105(5) Å, and β=95.6510(10)°. Although the two structures are different, they have the same anionic framework compositions of [Zn3(HPO3)4]2−. Their frameworks are built up from strictly alternating ZnO4 tetrahedra and HPO3 pseudo pyramids by sharing vertexes. There exist channels with an eight-membered ring window along the a- and c-axis. Powder X-ray diffraction, IR spectroscopy, 31P MAS solid-state NMR, thermogravimetric and differential thermal analyses were also carried out.  相似文献   

12.
The crystal structures of 1,4-diazabicyclo[2.2.2]octane (dabco)-templated iron sulfate, (C6H14N2)[Fe(H2O)6](SO4)2, were determined at room temperature and at −173 °C from single-crystal X-ray diffraction. At 20 °C, it crystallises in the monoclinic symmetry, centrosymmetric space group P21/n, Z=2, a=7.964(5), b=9.100(5), c=12.065(5) Å, β=95.426(5)° and V=870.5(8) Å3. The structure consists of [Fe(H2O)6]2+ and disordered (C6H14N2)2+ cations and (SO4)2− anions connected together by an extensive three-dimensional H-bond network. The title compound undergoes a reversible phase transition of the first-order at −2.3 °C, characterized by DSC, dielectric measurement and optical observations, that suggests a relaxor–ferroelectric behavior. Below the transition temperature, the compound crystallizes in the monoclinic system, non-centrosymmetric space group Cc, with eight times the volume of the ambient phase: a=15.883(3), b=36.409(7), c=13.747(3) Å, β=120.2304(8)°, Z=16 and V=6868.7(2) Å3. The organic moiety is then fully ordered within a supramolecular structure. Thermodiffractometry and thermogravimetric analyses indicate that its decomposition proceeds through three stages giving rise to the iron oxide.  相似文献   

13.
Two new mixed organic-inorganic uranyl molybdates, (C6H14N2)3[(UO2)5(MoO4)8](H2O)4 (1) and (C2H10N2)[(UO2)(MoO4)2] (2), have been obtained by hydrothermal methods. The structure of 1 [triclinic, , Z=1, a=11.8557(9), b=11.8702(9), c=12.6746(9) Å, α=96.734(2)°, β=91.107(2)°, γ=110.193(2)°, V=1659.1(2) Å] has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1=0.058, which was calculated for the 5642 unique observed reflections (|Fo|?4σF). The structure contains topologically novel sheets of uranyl square bipyramids, uranyl pentagonal bipyramids, and MoO4 tetrahedra, with composition [(UO2)5(MoO4)8]6−, that are parallel to (−101). H2O groups and 1,4-diazabicyclo [2.2.2]-octane (DABCO) molecules are located in the interlayer, where they provide linkage of the sheets. The structure of 2 [triclinic, , Z=2, a=8.4004(4), b=11.2600(5), c=13.1239(6) Å, α=86.112(1)°, β=86.434(1)°, γ=76.544(1)°, V=1203.14(10) Å] has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1=0.043, which was calculated for 5491 unique observed reflections (|Fo|?4σF). The structure contains topologically novel sheets of uranyl pentagonal bipyramids and MoO4 tetrahedra, with composition [(UO2)(MoO4)2]2−, that are parallel to (110). Ethylenediamine molecules are located in the interlayer, where they provide linkage of the sheets. All known topologies of uranyl molybdate sheets of corner-sharing U and Mo polyhedra can be described by their nodal representations (representations as graphs in which U and Mo polyhedra are given as black and white vertices, respectively). Each topology can be derived from a simple black-and-white graph of six-connected black vertices and three-connected white vertices by deleting some of its segments and white vertices.  相似文献   

14.
A new 3-D inorganic-organic hybrid framework microporous material Zn3(bbdc)3(4,4′-bpy)·2(DMF)·4(H2O) (1), which is constructed by coordination of zinc ions with 4,4′-bibenzene-dicarboxylic acid (H2bbdc) and 4,4′-bipyridine (4,4′-bpy), was obtained at mild synthesis condition. Crystallographic data for the compound (1), C58H54N4O18Zn3, orthorhombic, space group Pbcn, a=14. 532(3) Å, b=25.037(5) Å, c=18.184(4) Å, Z=4, V=6616(2) Å3.  相似文献   

15.
Employing 1-(2-Aminoethyl) piperazine as a template, a new organically templated layered zinc phosphate-phosphite (C6H17N3)[Zn4(PO4)2(HPO3)2] has been prepared hydrothermally. Single-crystal X-ray diffraction analysis shows that it crystallizes in the monoclinic space group Cc with a=5.3272(11) Å, b=17.146(3) Å, c=22.071(4) Å, β=94.58(3)°, V=2009.5(7) Å3, Z=4, R1=0.0201 (I>2σ(I)) and wR2=0.0812 (all data). The inorganic network is based on strictly alternating ZnO4 tetrahedral units and P-centered units including PO4 tetrahedra and HPO3 pseudo-pyramids forming a double layered structure that contains columns of double six-membered rings. The diprotonated 1-(2-Aminoethyl) piperazine molecules reside in the interlayer region and interact with the inorganic network through H-bonds.  相似文献   

16.
合成了高氯酸镨和咪唑(C3H4N2), DL-α-丙氨酸(C3H7NO2)混配配合物晶体. 经傅立叶变换红外光谱、化学分析和元素分析确定其组成为[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3. 使用具有恒温环境的溶解-反应量热计, 以2.0 mol•L-1 HCl为量热溶剂, 在T=(298.150±0.001) K时测定出化学反应PrCl3•6H2O(s)+2C3H7NO2(s)+C3H4N2(s)+3NaClO4(s)=[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(1)的标准摩尔反应焓为ΔrHmө=(39.26±0.11) kJ•mol-1. 根据盖斯定律, 计算出配合物的标准摩尔生成焓为ΔfHmө{[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3(s), 298.150 K}=(-2424.2±3.3) kJ•mol-1. 采用TG-DTG技术研究了配合物在流动高纯氮气(99.99%)气氛中的非等温热分解动力学, 运用微分法(Achar-Brindley-sharp和Kissinger法)和积分法(Satava-Sestak和Coats-Redfern法)对非等温动力学数据进行分析, 求得分解反应的表观活化能E=108.9 kJ•mol-1, 动力学方程式为dα/dt=2(5.90×108/3)(1-α)[-ln(1-α)]-1exp(-108.9×103/RT).  相似文献   

17.
The energy-localized CNDO/2 molecular orbitais have been calculated for the clusters containing molybdenum, > {Mo3S42Mo}8+ and> Mo3S4]CuI> 4+, versus the prototype arene-metal sandwich (C6H6)2Cr and half-sandwich complexes C6H6Cr(CO)3. The bonding characteristics of these compounds are described from a localization bonding viewpoint. There are two typical M-arene and M-[Mo3S4] bondings. One is formed by electron donation from the three-center two-electron π-bonds in the arene or [Mo3S4]4+ ligands into the vacant hybrid orbitais of the “stranger” metal atom. In the other M-arene or M-[Mo3S4] bond there is very little donation by the lone electron pair occupying the d AOs of the “stranger” metal atom to the arene or [Mo3S4]4+ ligands. The analogy of the ligand [Mo3S4]4+ in the clusters studied with the ligand benzene is also briefly discussed.  相似文献   

18.
Two new salts of malonic acid have been prepared: the copper(II) malonate tetrahydrate and the copper(II)-ammonium double malonate. Their study by thermal analysis (TG and DTA) leads to the following results:Cu(C3H2O4)·4H2O: the dehydration is rather complex and it is only under careful conditions that an intermediate hydrate Cu(C3H2O4)·3H2O could be traced. At about 170°C the dehydration is not ended (the salt holds yet about 0.15H2O) and the anhydrous salt occurs only at about 240°C. It decomposes immediately leading to residues the composition of which depends upon the surrounding atmosphere; the part played by the gas given off is discussed.Cu(NH4)2(C3H2O4)2: this salt melts and decomposes simultaneously at about 190°C. During the decomposition the copper nitride Cu3N forms as intermediate compound (as well as copper metal). Concerning the final residues of the decomposition the results and the conclusions are the same as the ones of the previous case.  相似文献   

19.
20.

Abstract  

The 18-metallacrown-6 metallamacrocycle [Fe6(pmshz)6(C4H9NO)6] has been synthesized by the self-assembly reaction of iron ions with N-substituted salicylhydrazide ligands. Six Fe(III) ions and six deprotonated N-propanoyl-4-methylsalicylhydrazide (H3 pmshz) ligands construct a planar 18-membered ring based on Fe–N–N–Fe linkage. Because of the coordination, the ligand enforces the stereochemistry of the Fe(III) ions as a propeller shape with alternating …ΔΛΔΛ… configurations. There is a strong antiferromagnetic exchange interaction between the paramagnetic iron centers.  相似文献   

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