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1.
Two modifications of the new uranyl oxalate hydroxide dihydrate [UO2)2(C2O4)(OH)2(H2O)2] (1 and 2) and one form of the new uranyl oxalate hydroxide trihydrate [(UO2)2(C2O4)(OH)2(H2O)2]·H2O (3) were synthesized by hydrothermal methods and their structures determined from single-crystal X-ray diffraction data. The crystal structures were refined by full-matrix least-squares methods to agreement indices R(wR)=0.0372(0.0842) and 0.0267(0.0671) calculated for 1096 and 1167 unique observed reflections (I>2σ(I)), for α (1) and β (2) forms, respectively and to R(wR)=0.0301(0.0737) calculated for 2471 unique observed reflections (I>2σ(I)), for 3. The α-form of the dihydrate is triclinic, space group , Z=1, a=6.097(2), b=5.548(2), , α=89.353(5), β=94.387(5), γ=97.646(5)°, , β-form is monoclinic, space group C2/c, Z=4, a=12.180(3), b=8.223(2), , β=95.817(4), . The trihydrate is monoclinic, space group P21/c, Z=4, a=5.5095(12), b=15.195(3), , β=93.927(3), . In the three structures, the coordination of uranium atom is a pentagonal bipyramid composed of dioxo UO22+ cation perpendicular to five equatorial oxygen atoms belonging to one bidentate oxalate ion, one water molecule and two hydroxyl ions in trans configuration in 2 and in cis configuration in 1 and 3. The UO7 polyhedra are linked through hydroxyl oxygen atoms to form different structural building units, dimers [U2O10] obtained by edge-sharing in 1, chains [UO6] and tetramers [U4O26] built by corner-sharing in 2 and 3, respectively. These units are further connected by oxalate entities that act as bis-bidentate to form one-dimensional chains in 1 and bi-dimensional network in 2 and 3. These chains or layers are connected in frameworks by hydrogen-bond arrays.  相似文献   

2.
Novel anhydrous trinuclear 3-oxo complexes of Cr(III), Cr3(3-O)(CF3COO)6(CH3COOH)2(CF3COO) (I) and of Cr(III,III,II), Cr3(3-O)(CF3COO)6(CH3COOH)2(THF) (II) (where THF is (CH2)4O) are synthesized by anodic dissolution of metallic chromium in solutions of trifluoroacetic acid in acetonitrile and in tetrahydrofuran and their structures are studied by X-ray diffraction analysis. Complex I forms orthorhombic crystals with space group Pna21, a = 9.778(1) , b = 16.042(2) , c = 22.851(4) , Z = 4, R 1 = 0.0332; complex II crystallizes in monoclinic system: space group P21/c, a = 9.866(1) , b = 17.895(2) , c = 21.167(4) , = 100.75(2)°, Z = 4, R = 0.0422. The average Cr-(3-O) distances in compounds I and II are almost equal (1.943(3) and 1.927(3) ). An average length of the Cr-O bond in octahedral surrounding of metal atoms is different in complexes I and II (1.985(4) and 2.003(3) , respectively), which is specified by different oxidation states of the metal atom. The CrCr distances lie in an interval of 3.366(1)–3.337(1) .__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 4, 2005, pp. 266–272.Original Russian Text Copyright © 2005 by Glazunova, Boltalin, Troyanov.  相似文献   

3.
Bis(citrato)hydroxogermanic(IV) acid was obtained for the first time in the complex [H5O2][Ge(H2Cit)(H2.5Cit)(OH)]2 · 2CH3COOH · 2H2O (H4Cit is citric acid). The complex was characterized by chemical analysis, X-ray powder diffraction, TGA, and IR spectroscopy. Complex I was studied by X-ray crystallography. The crystals are triclinic; a = 10.0651(4) ?, b = 10.1918(4) ?, c = 10.5838(4) ?, α = 85.0110(10)°, β = 85.2170(10)°, γ = 86.7670(10)°, V = 1076.50(7) ?3, Z = 1, space group P[`1]P\bar 1, R1 = 0.0353 for 5709 reflections with I > 2σ(I). Complex I is composed of centrosymmetric dimeric complex anions [Ge2(H2Cit)2(H2.5Cit)2(OH)2], dioxonium cations [H5O2]+, and acetic acid and water molecules of crystallization. The coordination polyhedron of the Ge atom is a trigonal bipyramid. Its equatorial plane comprises two O atoms of the deprotonated alcohol groups of two ligands H2Cit (A) and H2.5Cit (B) and the O atom of the terminal OH group (Ge-O, 1.7585–1.7754 ?; OeqGe(1)Oeq, 116.26°–127.64°). The axial positions are occupied by the carboxy O atom of the deprotonated carboxylate group of the α branch of ligand A (α-Ge-O(C)(carb), 1.8882(12) ?)) and the carbonyl O atom of the hemiprotonated acetate α branch of ligand B (α-Ge-O(C) 1.9615(12) ?, O(1)Ge(1)O(8) 170.47(5)°). In structure I, the complex dianion, the cation, and acetic acid and water molecules are united through hydrogen bonds into a three-dimensional framework.  相似文献   

4.
Highly uniform, porous β-Co(OH)2 nanostructures with an appearance reminding of certain spherical corals were synthesized via a facile, one-step hydrothermal route using ethanol-water mixtures as solvents. The rough surfaces of the nanostructures consist of numerous randomly distributed, interconnecting nanoflakes, resulting in a network-like structure with many cavities. The coral-like product has a high Brunauer-Emmet-Teller specific surface area of 163 m2/g. The diameter of the coral-like β-Co(OH)2 nanostructures is adjustable from 800 nm to 2 μm. The effects of the ethanol/water ratio, the Co2+ concentration, the hydrothermal temperature, and the reaction time on the formation of the coral-like structures were investigated. Cyclic voltammetry and galvanostatic charge-discharge tests show that the β-Co(OH)2 possesses excellent capacitive properties. This is mainly attributed to the high porosity, which allows a deep penetration by electrolytes.  相似文献   

5.
The structures of the crystals of Ba4[trans(N)-Co(Ida)2]3[cis-(N)-Co(Ida)2]2(ClO4)3 · 19.46H2O · 2CH3OH (I) and Ba[trans-(N)-Co(Ida)2]2 · 7H2O (II) (H2Ida is iminodiacetic acid) were determin by X-ray diffraction. The crystals of I containing two geometric isomers of the complex anions [Co(Ida)2] were obtained by a slow cooling of a hot solution, which contained initially only the cis-isomer. One Ba atom in I interacts with the trans-complex and with two cis-complexes to give a three-dimensional framework in crystal I. The positive charge of the last framework is compensated by one more trans-complex and by the perchlorate ions, one of which acts as a bidentate ligand with respect to the Ba atom. The crystals of II are built of the chains with the alternating Ba atoms and the trans-(N)-[Co(Ida)2] anions. The other anions of the same structure are each “suspended” to the Ba atoms of the chain. Original Russian Text ? M. Zabel, A.I. Poznyak, V.I. Pawlowskii, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 11, pp. 831–836.  相似文献   

6.
The novel 3D coordination polymer {Cd2(C4H2O4)2(C4H6N2)2(H2O)2 · 2H2O} n (I) has been synthesized and characterized by standard solid state methods including single-crystal X-ray crystallography. The compound crystallizes in triclinic space group P [`1]\bar 1 with a = 8.589(4), b = 10.585(3), c = 13.094(1) ?, α = 84.91(4)°, β = 79.21(0)°, γ = 83.76(4)°, V = 1159.5(1) ?3, Z = 2. The fumaric acid acts as a multimodal bridging ligand in the polymer unit. One of the fumaric acid ligands tridentately chelates to two Cd2+ cations in the same dinuclear unit, while the other bidentately chelates to two Cd2+ cations in another dinuclear unit. The two metal centers possess slightly distorted pentagonal bipyramid geometry with four Cd {(μ4-fumarato)-(μ2-fumarato)-bis(2-methylimidazolyl)-diaqua} units joining together to form a 28-membered ring. The whole molecule exhibits a through channel along y-axis and 2D layers in xz plane. With hydrogen bond and π-π interaction, the 2D layers construct a 3D microporous network.  相似文献   

7.
A novel heterotrimetallic complex {[(Dipic)2Cu]4 · Mg(H2O)2Na4(H2O)14 n · nNa2(H2O)10 · 2nCH3OH (H2Dipic = pyridine-2,6-dicarboxylic acid) has been synthesized and structurally determined by X-ray diffraction method. The compound crystallizes in the triclinic system, space group P [`1]\bar 1, with a = 13.5523(13), b = 14.1859(13), c = 14.3213(14) ?, α = 62.6160(10)°, β = 68.2540(10)°, γ = 89.7110(10)°, V = 2224.7(4)?3, F(000) = 1144, M r = 2237.70, Z = 1, ρ c = 1.670 g cm−3, μ = 1.095 mm−1, final R = 0.0507, wR = 0.1418 for 8042 independent reflections with R int = 0.0228. According to the structure determination, the complex is composed of novel one-dimensional (1D) alternating chains, dinuclear Na(I) units, and lattice methanol molecules. The infinite 1D chain structure is built up with many of polymeric [(Dipic)2Cu]4 · Mg(H2O)2Na4(H2O)14 units, which consists of four six-coordinated Cu2+ ions, one six-coordinated Mg2+ ion, two five-coordinated Na+ ions, and two six-coordinated Na+ ions. The 1D alternating chains are linked with another dinuclear Na(I) units by extensive hydrogen bonds to form a three-dimensional (3D) supramolecular structure in which uncoordinated methanol molecules act as space filling particles.  相似文献   

8.
[Mn2(CHZ)4(H2O)2](PA)4·10H2O的制备和分子结构研究   总被引:10,自引:0,他引:10  
本文论述了苦味酸(PA,三硝基苯酚)锰与碳酰肼(CHZ, NH2NHCONHNH2)反应制备目标配合物的方法及该配合物的晶体结构。该配合物的结构式为[O,O′-μ-Mn2(CHZ)4(H2O2)](PA)4·10H2O。晶体属三斜晶系,P1 空间群。晶体学参数为:a=0.8269(1) nm, b=1.2812(1) nm, c=1.5915(1) nm; α=109.58(1)°, β=95.19(1)°, γ=92.76(1)°, V=1.5765(2)nm3; Z=1, Dc=1.580 g·cm-3, μ(Mo Kα)=520 m-1。晶体结构经全矩阵最小二乘法修正,最终偏离因子R=0.0557。该化合物为具有中心对称的双核配合物,以两个碳酰肼分子中羰基氧为桥原子将两个锰离子结合起来,与锰离子形成配位键的原子是碳酰肼分子第一、五氮原子,羰基氧原子和水分子中的氧原子,锰离子的配位数为七。若味酸根作为外界离子以库伦力和氢键与内界离子结合成配合物分子。  相似文献   

9.
10.
Complexes Zn(H2O)4(L) (I) and Zn(H2O)(L) (II) (H2L = p-HOOCC6F4COOH) are synthesized. Single crystals of compound [Zn(H2O)4(L) · 4H2O] n (III) are grown. According to the X-ray diffraction data, the crystal structure of compound III is built of zigzag chains of coordination polymer Zn(H2O)4(L) and molecules of water of crystallization. The chain contains ions Zn2+, whose octahedral coordination sphere includes the O atoms of four water molecules and two O atoms of the deprotonated carboxyl groups. The chains in structure III are joined by a system of hydrogen bonds of coordinated water molecules and molecules of water of crystallization. The photoluminescence spectrum of H2L exhibits the band with λmax = 368 nm. The spectra of compounds III, I, and II contain bands at 322, 340, and 353 nm, respectively.  相似文献   

11.
Two novel cyano-bridged complexes, {[Cu(men)2][Ni(CN)4] n (1) (men = N,N′-dimethyl-ethylenediamine) and [Mn(bpy)2]4[Mo(CN)8]2·0.5MeOH·0.75H2O (2) (bpy = 2,2′-bipyridine) have been synthesized and structurally characterized by IR spectroscopy and X-ray crystallography. The complex 1 has onedimensional zigzag chain structure in which the Ni atom is coordinated by four cyanide groups, and the Cu atom is surrounded by four nitrogen atoms of the two men ligands in equatorial plane and two nitrogen atoms of the bridging cyanide in axial positions; the Cu centre is in a distorted octahedral environment. Owing to weak interactions, complex 1 is self-assembled into two-dimensional network via N-H...N hydrogen bonds. In 2, the basic structural unit is centrosymmetric and contains four Mn centers connected by two octacyanomolybdates via eight cyanide bridges. Each Mo atom is linked via four cyanide groups to four Mn, and the other four cyanide groups are terminal. From X-ray single crystal analysis (room temperature), 1 crystallizes in monoclinic space group P21/n with a = 6.7332(7) ?, b = 13.9248(15) ?, c = 9.0869(10) ?, β = 98.4030(10)°, V = 843.05(16) ?3, Z = 2; 2 crystallizes in monoclinic space group P21/n with a = 13.886(6) ?, b = 24.116(11) ?, c = 15.263(7) ?, β = 90.175(6)°, V = 5111(4) ?3, Z = 2. Original Russian Text Copyright ? 2009 by X. Chen, P. Yang, S.-L. Ma, S. Ren, M.-Y. Tang, Y. Yang, Z.-J. Guo, and L.-Z. Liu The text was submitted by the authors in English. Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 518–521, May–June, 2009.  相似文献   

12.
A novel inorganic-organic hybrid material, [Cu(En)2]2H2[{Cu(En)2}2(H2W12O42)] · 6.5H2O (I) based on polyoxotungstates and Cu2+ ions, has been successfully synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, IR spectra, and TG analysis. Structural analysis indicates that the structure consists of a one-dimensional structure constructed from the polyoxoanion [H2W12O42]10− bridged by {Cu(En)2}2+ groups. Each [H2W12O42]10− cluster in the polymeric chain is linked to two neighbors through four coordination groups of μ2-[Cu(En)2]2+. Furthermore, it extends into a three-dimensional supramolecular network by hydrogen bonding interactions.  相似文献   

13.
New mixed-ligand coordination compounds[Cd(DMSO)5(NCS)][Cr(NH3)2(NCS)4] · 3DMSO (I) and [Mn(DMSO)4(H2O)2][Cr(NH3)2(NCS)4]2 · 6DMSO · 2H2O (II) have been synthesized and studied by IR spectroscopy and X-ray diffraction analysis. The crystals of compound I are monoclinic, a = 14.5275(7), b = 23.1692(11), c = 14.6969(6) ?, β = 97.057(2)°, V = 4909.4(4) ?3, space group P21/c, Z = 4, ρcalcd = 1.507 g/cm3, R = 0.0556. The crystals of compound II are triclinic, a = 11.7784(3), b = 12.1760(3), c = 13.1922(2) ?, α = 85.5420(10)°, β = 87.9000(10)°, γ = 70.3680(10)°, V = 1776.46(7) ?3, space group P , Z = 1, ρcalcd = 1.444 g/cm3, R = 0.0350. Original Russian Text ? E.A. Gerasimova, T.V. Utkina, E.V. Peresypkina, A.V. Virovets, T.G. Cherkasova, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 5, pp. 751–755.  相似文献   

14.
A procedure for the synthesis of the heteropolymetallic germanium(IV) and copper(II) complex with trihydroxyglutaric acid (H5Thgl) [Cu(H2O)6][Ge(μ3-Thgl)2{Cu(H2O)2}2] · 2H2O (I) was developed and the complex was isolated for the first time in the solid state. The product was characterized by elemental analysis, powder X-ray diffraction, thermogravimetry, and IR spectroscopy. Compound I was studied by X-ray crystallography. The crystals are monoclinic, a = 10.216(2)?, b = 12.272(3)?, c = 10.679(2)?, β = 93.13(3)°, V = 1336.9(5)?3, Z = 2, space group P21/n, R1 = 0.0261 for 3616 reflections with I > 2σ(I). Compound I is composed of bimetallic [Ge(μ3-Thgl)2{Cu(H2O)2}2]2− anions, [Cu(H2O)6]2+ cations, and water molecules of crystallization. In the centrosymmetric trinuclear complex anion, the Ge(1) atom is bound by two fully deprotonated bridging ligands to two Cu atoms. The Ge(1) atom is coordinated at distorted octahedron vertices by six hydroxyl oxygen atoms of two Thgl5− ligands (average Ge(1)-O distance is 1.8874(13)?). The Cu coordination polyhedron in the anion is an extended square pyramid (4 + 1) formed by the bridging hydroxyl oxygen atom (Cu(1)-O(3), 2.0039(12) ?), two carboxyl oxygen atoms (average CU(1)-O distance is 1.9674(14)?) of two Thgl5− ligands, and two water oxygen atoms in equatorial and axial positions (Cu(1)-O, 1.9761(13) and 2.3643(14)?, respectively). In the centrosymmetric cation, the Cu coordination polyhedron is an extended square bipyramid (4 + 2). The equatorial Cu-O bond length is 1.9428(14) ? (average), the axial Cu-O bond is elongated to 2.5151(14)?. The cations and anions are combined by H-bonds.  相似文献   

15.
Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 298.15 K. Supported by the Research Fund of Beijing Institute of Petro-Chemical Technology (N06-06)  相似文献   

16.
The three-dimensional coordination polymers [Ni4(μ-H2O)2(nic)8 · 2H2O] (nic = nicotinate, 3-pyridylcarboxylate) (1) and [Ni2(H2O)2(nic)4(4,4′-bpy)] (2) were prepared by the hydrothermal reaction of nickel(II) chloride, nicotinic acid, sodium hydroxide and an organoimine (several choices for 1, 4,4′-bipyridine for 2). The non-centrosymmetric crystal structure of 1 is constructed from binuclear [Ni2(μ-H2O)(μ3-nic)2]2+ subunits joined into 3-D via μ2- and μ3-nicotinate ligands, forming “bird”-shaped cavities that contain water molecule dimers. The crystal structure of 1 is compared and contrasted to two previously reported nickel(II) nicotinate phases. In contrast, the crystal structure of 2 is assembled from neutral [Ni(H2O)(μ2-nic)2] layers, connected into 3-D via tethering 4,4′-bpy moieties. 1 exhibits weak antiferromagnetic coupling across its binuclear subunits (J = −1.61(2) cm−1 for g = 2.233(2)), although anisotropy due to single-ion zero-field-splitting (D) cannot be excluded. The 3-D structures of 1 and 2 remain stable above 300 °C and 200 °C, respectively.  相似文献   

17.
IR and single-crystal X-ray diffraction study are carried out for compound, C36H112Cl9Fe3N18O8P6(I). It crystallizes in the orthorhombic space group P212121 with a = 14.2992(3), b = 21.4351(4), c = 25.5407(5) ?, V = 7828.3(3) ?3, ρcalcd = 1.553 g/cm3, Z = 4. The FeCl fragment is coordinated with chlorine atom of two water molecules and three HMPA molecules to form a cation, with a distorted octahedral coordinate geometry. In the crystal I, the cation is linked with HMPA by the O-H…O hydrogen bond. The chiral crystal is formed through self-assembly even from achiral molecules.  相似文献   

18.
Two metal-organic coordination polymers [Cu(bpy)2(H2O)2](NO3)2·4.5C2H5OH (1) and [Cu2(bpy)(H2O)(L-pha) 2](NO3)2·H2O (2) (L-Hpha = L-phenylalanine, bpy = 4,4′-bipyridyl) are prepared by slow evaporation of an aqueous alcoholic solution of copper nitrate, L-phenylalanine, and 4,4′-bipyridyl. The structure and composition of the obtained compounds are determined by single crystal XRD. The framework of compound 1 is positively charged and forms two types of intersecting channels. Compound 2 is a homochiral metal-organic coordination polymer whose structure contains L-phenylalanine anions.  相似文献   

19.
Methods for the synthesis of trans-diammino complexes [RuNO(NH3)2(NO2)2(OH)] (I) and [RuNO(NH3)2(H2O)(NO3)2](NO3)·H2O (II) are suggested. The compounds were studied by IR spectroscopy and X-ray phase and X-ray structural analyses. Crystal data: space group P-1; a = 6.2328(2) ?, b = 11.0488(3) ?, c = 11.0981(4) ?, α = 71.942(1)°, β = 83.291(1)°, γ = 86.877(1)° (I); space group P21; a = 6.6290(2) ?, b = 13.4389(5) ?, c = 7.0180(2) ?, β 114.281(1)° (II). Complex II readily lost some part of crystal water on storage in open air. Original Russian Text Copyright ? 2009 by M. A. Il’in, E. V. Kabin, V. A. Emel’yanov, I. A. Baidina, and V. A. Vorob’yov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 341–348, March–April, 2009.  相似文献   

20.
The polymeric coordination compound {[Ge(μ-HCit)2Ba(H2O)3] · 3H2O} n (H4Cit = citric acid) was obtained for the first time for germanium(IV) citrates. The compound was characterized by elemental analysis, thermogravimetry, IR spectroscopy, and X-ray crystallography. Crystals of the compound are triclinic, a = 7.422(4) ?, b = 10.668(4) ?, c = 14.342(6) ?, α = 91.31(3)°, β = 95.81(4)°, γ = 104.08(4)°, V = 1094.5(8) ?3, Z = 2, space group P $ \bar 1 $ \bar 1 , R1 = 0.0479 for 2284 reflections with I > 2σ(I). Two crystallographically independent octahedral [Ge(HCit)2]2− anions are linked by Ba2+ ions to form a polymeric chain. The coordination number of Ba atoms is equal to 9. The chains are linked to each other and crystal water molecules by hydrogen bonds.  相似文献   

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