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1.
Wheely: For the first time and very unexpectedly, a rupture of the very stable {P(8)W(48)} wheel was observed in aqueous solution at pH?4 and 80?°C in the presence of Fe(III), Eu(III)/Gd(III), and H(2)O(2). This inorganic ring opening is unprecedented in polyoxometalate chemistry.  相似文献   

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The reaction of K28Li5H7[P8W48O184].92H2O with early lanthanides under hydrothermal and conventional conditions yields novel structures of the molecular formula Ln4(H2O)28K6Li7[K subsetP8W48O184(H4W4O12)2Ln2(H2O)10] congruent with 57H2O, Ln = La (1), Ce (2, 2a), Pr (3), Nd (4), in which the central cavity of the precursor anion is occupied by lanthanide cations and H4W4O12 moieties. The new heteropolyanions were characterized by elemental analysis, infrared spectroscopy, 31P NMR, and X-ray crystallography. All of the crystals are monoclinic, space group C2/m, with lattice constants (A, Epsilon) a = 33.061(3), b = 30.986(3), c = 15.1649(13), beta = 103.607(2), (1); a = 33.0577(16), b = 31.0562(15), c = 15.2320(7), beta = 104.015(2), (2); a = 33.0577(16), b = 31.0562(15), c = 15.2320(7), beta = 104.015(2), (2a); a = 33.007(2), b = 31.060(2), c = 15.2129(10), beta = 104.0140(10), (3); a = 32.913(19), b = 31.155(18), c = 15.135(9), beta = 103.495(11), (4); and Z = 2.  相似文献   

4.
Two new iron–oxo clusters, viz. di‐μ‐tri­fluoro­acetato‐μ‐oxo‐bis­[(2,2′‐bi­pyridine‐κ2N,N′)(tri­fluoro­acetato‐κO)­iron(III)], [Fe2O(CF3CO2)4(C10H8N2)2], and bis(2,2′‐bi­pyridine)­di‐μ3‐oxo‐hexa‐μ‐tri­fluoro­acetato‐bis­(tri­fluoro­acetato)­tetrairon(III) tri­fluoro­acetic acid solvate, [Fe4O2(CF3CO2)8(C10H8N2)2]·CF3CO2H, contain dinuclear and tetranuclear FeIII cores, respectively. The FeIII atoms are in distorted octahedral environments in both compounds and are linked by oxide and tri­fluoro­acetate ions. The tri­fluoro­acetate ions are either bridging (bidentate) or coordinated to the FeIII atoms via one O atom only. The fluorinated peripheries enhance the solubility of these compounds. Formal charges for all the Fe centers were assigned by summing valences of the chemical bonds to the FeIII atom.  相似文献   

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6.
The pale‐rose compound [(μ‐C6H8O4)4/2Co(μ‐H2O)2Co(H2O)4] · 4 H2O was prepared from adipic acid and CoCO3 in aqueous solution. The crystal structure (monoclinic, P21/n (no. 14), a = 8.061(1), b = 15.160(2), c = 9.708(2) Å, β = 90.939(7)°, Z = 2, R = 0.0405, wR2 = 0.0971) consists of adipate bridged supramolecular [(μ‐C6H8O4)4/2Co(μ‐H2O)2Co(H2O)4] layers and hydrogen bonded H2O molecules. The cobalt atoms Co1 and Co2 are distorted octahedrally coordinated by the O atoms of two bridging trans‐H2O molecules and four bidentate adipate anions (Co1) and by the O atoms of two bridging trans‐H2O molecules and four monodentate H2O molecules (Co2), respectively. Equatorial bonds: d(Co1–O) = 2.048 Å (2 × ), 2.060 Å (2 × ); d(Co2–O) = 2.057 Å (2 × ), 2.072 Å (2 × ). Axial bonds: d(Co1–O) = 2.235 Å (2 × ); d(Co2–O) = 2.156 Å (2 × ).  相似文献   

7.
Reaction of MnSO4 · H2O, 2,2′‐bipyridine (bpy), suberic acid and Na2CO3 in CH3OH/H2O yielded a mixture of [Mn2(H2O)4(bpy)2(C8H12O4)2] · 2 H2O ( 1 ) and [Mn(H2O)2‐ (bpy)(C8H12O4)2/2] · H2O ( 2 ). In both complexes, the Mn atoms are octahedrally coordinated by two N atoms of one bpy ligand and four O atoms of two trans positioned H2O molecules and two suberato ligands (d(Mn–O) = 2.107–2.328 Å; d(Mn–N) = 2.250–2.330 Å). The bis‐monodentate suberato ligands bridge Mn atoms to form dinuclear [Mn2(H2O)4(bpy)2(C8H12O4)2] complex molecules in 1 and 1D [Mn(H2O)2(bpy)(C8H12O4)2/2] chains in 2 . Via the intermolecular hydrogen bondings and π‐π stacking interactions, the dinuclear molecules in 1 are assembled into 2D networks parallel to (100), between which the crystal H2O molecules are sandwiched. The polymeric chains in 2 are linked together by interchain hydrogen bonding and π‐π stacking interactions into 3D networks with the crystal H2O molecules located in tunnels along [010]. Crystal data for 1 : P21/c (no. 14), a = 10.092(1) Å, b = 11.916(2) Å, c = 17.296(2) Å, β = 93.41(1)° and Z = 2. Crystal data for 2 : P21/c (no. 14), a = 11.176(2) Å, b = 9.688(1) Å, c = 37.842(6) Å, β = 90.06(1)° and Z = 8.  相似文献   

8.
(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands.  相似文献   

9.
Reactions of 1,10‐phenanthroline monohydrate, Na2C4H4O4 · 6 H2O and MnSO4 · H2O in CH3OH/H2O yielded a mixture of [Mn2(H2O)4(phen)2(C4H4O4)2] · 2 H2O ( 1 ) and [Mn(phen)2(H2O)2][Mn(phen)2(C4H4O4)](C4H4O4) · 7 H2O ( 2 ). The crystal structure of 1 (P1 (no. 2), a = 8.257(1) Å, b = 8.395(1) Å, c = 12.879(2) Å, α = 95.33(1)°, β = 104.56(1)°, γ = 106.76(1)°, V = 814.1(2) Å3, Z = 1) consists of the dinuclear [Mn2(H2O)4(phen)2(C4H4O4)2] molecules and hydrogen bonded H2O molecules. The centrosymmetric dinuclear molecules, in which the Mn atoms are octahedrally coordinated by two N atoms of one phen ligand and four O atoms from two H2O molecules and two bis‐monodentate succinato ligands, are assembled via π‐π stacking interactions into 2 D supramolecular layers parallel to (101) (d(Mn–O) = 2.123–2.265 Å, d(Mn–N) = 2.307 Å). The crystal structure of 2 (P1 (no. 2), a = 14.289(2) Å, b = 15.182(2) Å, c = 15.913(2) Å, α = 67.108(7)°, β = 87.27(1)°, γ = 68.216(8)°, V = 2934.2(7) Å3, Z = 2) is composed of the [Mn(phen)2(H2O)2]2+ cations, [Mn(phen)2(C4H4O4)] complex molecules, (C4H4O4)2– anions, and H2O molecules. The (C4H4O4)2– anions and H2O molecules form 3 D hydrogen bonded network and the cations and complex molecules in the tunnels along [001] and [011], respectively, are assembled via the π‐π stacking interactions into 1 D supramolecular chains. The Mn atoms are octahedrally coordinated by four N atoms of two bidentate chelating phen ligands and two water O atoms or two carboxyl O atoms (d(Mn–O) = 2.088–2.129 Å, d(Mn–N) = 2.277–2.355 Å). Interestingly, the succinato ligands in the complex molecules assume gauche conformation bidentately to chelate the Mn atoms into seven‐membered rings.  相似文献   

10.
In the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)2 · MgSO4 · 8H2O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)2‐MgSO4‐H2O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) Å3]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH2)2(OH)4 octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO4 tetrahedra and interstitial water molecules separate the stacks of parallel double chains.  相似文献   

11.
The complexes cis‐[SnCl4(H2O)2]·2H2O ( 1 ), [Sn2Cl6(OH)2(H2O)2]·4H2O ( 3 ), and [HL][SnCl5(H2O)]·2.5H2O ( 4 ) were isolated from a CH2Cl2 solution of equimolar amounts of SnCl4 and the ligand L (L=3‐acetyl‐5‐benzyl‐1‐phenyl‐4, 5‐dihydro‐1, 2, 4‐triazine‐6‐one oxime, C18H18N4O2) in the presence of moisture. 1 crystallizes in the monoclinic space group Cc with a = 2402.5(1) pm, b = 672.80(4) pm, c = 1162.93(6) pm, β = 93.787(6)° and Z = 8. 4 was found to crystallize monoclinic in the space group P21, with lattice parameters a = 967.38(5) pm, b = 1101.03(6) pm, c = 1258.11(6) pm, β = 98.826(6)° and Z = 2. The cell data for the reinvestigated structures are: [SnCl4(H2O)2]·3H2O ( 2 ): a = 1227.0(2) pm, b = 994.8(1) pm, c = 864.0(1) pm, β = 103.86(1)°, with space group C2/c and Z = 4; 3 : a = 961.54(16) pm, b = 646.29(7) pm, c = 1248.25(20) pm, β = 92.75(1)°, space group P21/c and Z = 4.  相似文献   

12.
A gigantic Co14‐containing 36‐niobate, Na12K8[Co14(OH)16(H2O)8Nb36O106] ? 71H2O ( 1 ), has been prepared by the hydrothermal method and structurally characterized. Polyanion [Co14(OH)16(H2O)8Nb36O106]20? ( 1 a ) comprises a central Co7 core, surrounded by another seven isolated Co2+ ions and six Lindqvist‐type (Nb6O19) hexaniobate fragments. This is the first example of a high‐nuclear cobalt‐cluster‐containing polyoxoniobate. The photocatalytic H2 evolution activity of Pt‐loaded 1 was observed in methanol solution under irradiation using a 300 W Xe lamp.  相似文献   

13.
By slow evaporation of solutions containing Ln(ClO4)3 (Ln = Sm, Gd), H5IO6 and an excess of HClO4, crystals of the title compounds could be obtained. Their structures were determined by single‐crystal X‐ray diffraction. The compounds crystallize in the monoclinic crystal system, space group P21/c. They contain Ln3+ ions, which are coordinated by [H2I2O10]4— anions forming two‐dimensional, cationic networks. These are separated by perchlorate ions, forming a layered structure.  相似文献   

14.
Using DTA and X-ray phase diffraction methods, a diagram of phase equilibria established in two sections of a tricomponent oxide triangle Fe2O3-V2O5-WO3was constructed, that is, in the sections: Fe8V10W16O85-Fe2O3and Fe8V10W16O85-Fe2WO6. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
[Cd(H2O)3(C5H6O4)]·2H2O ( 1 ) and Cd(H2O)2(C6H8O4) ( 2 ) were prepared from reactions of fresh CdCO3 precipitate with aqueous solutions of glutaric acid and adipic acid, respectively, while Cd(H2O)2(C8H12O4) ( 3 ) crystallized in a filtrate obtained from the hydrothermal reaction of CdCl2·2.5H2O, suberic acid and H2O. Compound 1 consists of hydrogen bonded water molecules and linear {[Cd(H2O)3](C5H6O4)2/2} chains, which result from the pentagonal bipyramidally coordinated Cd atoms bridged by bis‐chelating glutarato ligands. In 2 and 3 , the six‐coordinate Cd atoms are bridged by bis‐chelating adipato and suberato ligands into zigzag chains according to {[Cd(H2O)3](C5H6O4)2/2} and {[Cd(H2O)2](C8H12O4)2/2}, respectively. The hydrogen bonds between water and the carboxylate oxygen atoms are responsible for the supramolecular assemblies of the zigzag chains into 3D networks. Crystallographic data: ( 1 ) P1¯ (no. 2), a = 8.012(1), b = 8.160(1), c = 8.939(1) Å, α = 82.29(1)°, β = 76.69(1)°, γ = 81.68(1)°, U = 559.6(1) Å3, Z = 2; ( 2 ) C2/c (no. 15), a = 16.495(1), b = 5.578(1), c = 11.073(1) Å, β = 95.48(1)°, U = 1014.2(1) Å3, Z = 4; ( 3 ) P2/c (no. 13), a = 9.407(2), b = 5.491(1), c = 11.317(2) Å, β = 95.93(3)°, U = 581.4(2) Å3, Z = 2.  相似文献   

16.
Reactions of di‐n‐butyltin(IV) oxide with 4′/2′‐nitrobiphenyl‐2‐carboxylic acids in 1 : 1 and 1 : 2 stoichiometry yield complexes [{(n‐C4H9)2Sn(OCOC12H8NO2?4′/2′)}2O]2 ( 1 and 2 ) and (n‐C4H9)2Sn(OCOC12H8NO2?4′/2′)2 ( 3 and 4 ) respectively. These compounds were characterized by elemental analysis, IR and NMR (1H, 13C and 119Sn) spectroscopy. The IR spectra of these compounds indicate the presence of anisobidentate carboxylate groups and non‐linear C? Sn? C bonds. From the chemical shifts δ (119Sn) and the coupling constants 1J(13C, 119Sn), the coordination number of the tin atom and the geometry of its coordination sphere have been suggested. [{(n‐C4H9)2Sn(OCOC12H8NO2?4′)}2O]2 ( 1 ) exhibits a dimeric structure containing distannoxane units with two types of tin atom with essentially identical geometry. To a first approximation, the tin atoms appear to be pentacoordinated with distorted trigonal bipyramidal geometry. However, each type of tin atom is further subjected to a sixth weaker interaction and may be described as having a capped trigonal bipyramidal structure. The diffraction study of the complex (n‐C4H9)2Sn(OCOC12H8NO2?4′)2 ( 3 ) shows a six–coordinate tin in a distorted octahedral frame containing bidentate asymmetric chelating carboxylate groups, with the n‐Bu groups trans to each other. The n‐Bu? Sn? n‐Bu angle is 152.8° and the Sn? O distances are 2.108(4) and 2.493(5) Å. The oxygen atom of the nitro group of the ligand does not participate in bonding to the tin atom in 1 and 3 . Crystals of 1 are triclinic with space group P1 and of that of 3 have orthorhombic space group Pnna. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

17.
An open-framework ammonium ferricborophosphate compound was synthesized by mild hydrothermal condition at 110°C. The crystal structure has been determined by single-crystal X-ray diffraction analysis: hexagonal, P6522, a = 9.452(2)A, c = 15.698(5)A,α = 90°,γ = 120°,Z= 6, Mr = 310.58, V = 1214.0(5)A3, Dc = 2.549 g/cm3, μ= 2.311mm-1, F(000) = 930. The chiral tetrahedral-tetrahedral helical ribbons are linked by the mixed valance FeII/FeIIIO6 coordinated octahedra. The ammonium ions are located inside the free loop of helical ribbons close to the inner wall of the helical channels{[BP2O8]3-}, effecting on balancing charge and stabilizing helical ribbons.  相似文献   

18.
Oxalato‐ and Squarato‐Bridged Threedimensional Networks: The Crystal Structures of La2(C2O4)(C4O4)2(H2O)8 · 2.5 H2O and K[Bi(C2O4)2] · 5 H2O The title compounds have been formed by hydrolysis of amino‐ and thioderivatives of squaric acid in the presence of LaIII and BiIII ions. Both compounds are threedimensional coordination polymers in the solid state, as shown by single crystal X‐ray crystallography. In La2(C2O4)(C4O4)2(H2O)8 · 2.5 H2O oxalato‐bridged pairs of LaO9 polyhedra are connected with identical neighbouring polyhedra by squarate ions. In K[Bi(C2O4)2] · 5 H2O each Bi atom is fourfold linked to other Bi atoms by the oxalate ions. The resulting 3D network shows a diamond‐like topology with square‐shaped channels. In both structures the channels are partially filled by water molecules.  相似文献   

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20.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

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