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1.
The synthesis of a radical-cation salt based on a derivative of tetrathiafulvalene, (ET)2[3,3′-Cr(1,2-C2B9H11)2] (ET?=?bis(ethylenedithio)tetrathiafulvalenium), was accomplished by electrochemical anodic oxidation of ET in the presence of (Me4N)[3,3´-Cr(1,2-C2B9H11)2] in the galvanostatic regime. An electric conductivity σ (293 K)?=?7 × 10?3 Ohm?1 cm?1 with semiconductor activation energy Ea???0.1 eV in the range of 127–300 K was observed. The crystal structure of (ET)2[3,3′-Cr(1,2-C2B9H11)2] was determined by X-ray diffraction at 173 K, revealing the presence of structural tetramers in radical-cation stacks. The magnetic properties of the complex were investigated in the temperature range 1.8–300 K using magnetometry and EPR, showing that the magnetic structure of (ET)2[3,3′-Cr(1,2-C2B9H11)2] consists of two independent magnetic subsystems. Cation radicals form a rectangular magnetic lattice in the ab-plane with significant antiferromagnetic exchange interactions. The chromium bis(dicarbollide) anions are characterized by unusually strong positive zero-field splitting of the Cr(III) ions, which was confirmed by ab initio calculations.  相似文献   

2.
Crystals of Ba3[Co(Nta)2]2 · 10H2O (Nta3? is the ion of nitrilotriacetic acid) are obtained (monoclinic crystal system, a = 17.094(3), b = 13.1873(13), c = 21.490(3) Å, β = 98.457(18)°, Z = 4, space group I2/c). The crystal structure of the compound is determined by X-ray diffraction analysis. The crystals consist of the Ba2+ cations, water molecules, and [Co(Nta)2]3? anions in which the donor N and 2O atoms of each Nta3? ion are located at opposite faces of the coordination octahedron. The Co(1, 2) atoms are arranged in the inversion centers. The Ba atoms of the complexes form an intricate three-dimensional framework. One of the two crystallographically nonequivalent complexes binds eight Ba atoms, and another one binds six Ba atoms. The coordination number of the Ba(1) atoms (in the general position) is nine (three O atoms of water molecules and six O atoms of the carboxyl groups of five complexes), and that of the Ba(2) atoms (on the 2 axis) is 6 (two O atoms of water molecules and four O atoms of the carboxyl groups of four complexes).  相似文献   

3.
4.
Two opposite configuration (R/S) of chiral complexes (C8H11N)2 · Zn(OAc)2 (Ia and Ib—L-(−)-) and D-(+)-isomer) were synthesized by a simple one-pot method. The crystal structures of Ia and ib determined by X-ray crystallography.  相似文献   

5.
Diphenylguanidinium bis(citrato)germanate hydrate (HDphg)2[Ge(HCit)2] · 1.08H2O (I) was prepared for the first time (H4Cit is citric acid, Dphg is diphenylguanidine). The composition of I was determined using elemental analysis and thermogravimetry; the coordination sites of H4Cit and the protonation sites of Dphg were identified by IR spectroscopy. Compound I was studied by X-ray diffraction. The crystals are monoclinic, a = 11.179(2) Å, b = 7.6081(15) Å, c = 23.529(5) Å, β = 95.38(3)°, V = 1992.3(7) Å3, Z = 2, space group P21/c, R = 0.0339 for 2498 reflections with I>2σ(I). In the [Ge(HCit)2]2? complex anion, the Ge atom is bond to a distorted octahedral array of six O atoms of the two tridentate chelating HCit3? ligands (Ge-O, 1.8045–1.9555 Å). In the crystal of I, the anions and cations are combined into layers by a system of hydrogen bonds.  相似文献   

6.
New caprolactam dodecamolybdosilicate of the composition (C6H11NO)4.5Н4[SiМо12O40] (I) is synthesized. Chemical and crystallographic analyses, NMR and IR spectroscopic studies are performed. Compound I is found to crystallize in the monoclinic system with the space group P21/n. Unit cell parameters are: a = 19.945(4) Å, b = 13.340(3) Å, c = 28.110(6) Å, β = 110.75(3)°, ρcalc = 2.232 g/cm3, М = 2350.63, Z = 4, V = 6994(3) Å3.  相似文献   

7.
Heterometallic potassium and sodium trihydroxyglutaratogermanates of the formulas K4[Ge2(μ-Thgl)2(OH)2] · 4H2O (I) and Na4[Ge2(μ-Thgl)2(OH)2] · 5H2O (II) (H5Thgl is trihydroxyglutaric acid) were obtained for the first time and characterized by elemental analysis, X-ray powder diffraction, thermogravimetry, and IR spectroscopy. Complex I was examined by single-crystal X-ray diffraction. The crystals are triclinic; a = 7.5933(15) Å, b = 7.628(4) Å, c = 10.516(4) Å, α = 104.01(3)°, β = 101.041(17)°, γ = 97.50(3)°, V = 570.0(3) Å3, Z = 1, space group \(P\bar 1,R\bar 1 = 0.0479\) for 2848 reflections with I > 2σ (I). Complex I is made up of the centrosymmetric dimeric complex anions [Ge2(μ-Thgl)2(OH)2]4?, the potassium cations, and water molecules of crystallization. In the anion, the two Ge atoms are bridged by two fully deprotonated ligands Thgl5?. The coordination polyhedron of the Ge(IV) atom is a distorted trigonal bipyramid. Its equatorial plane is made up of the O atom of the terminal OH group (Ge-O…OH, 1.760(2) Å) and the O atoms of two alcohol groups of two ligands Thgl5? (av. Ge-Oalc, 1.797(2) Å; the angles OeqGe(1)Oeq, 110.12°–137.11°). The axial positions are occupied by the O atom of the alcohol group (Ge-Oalc, 1.853(2) Å) and the carboxyl O atom of one carboxylate group (Ge-Ocarb, 1.944(2) Å) of two symmetry-related ligands Thgl5?. The angle OaxGeOax is 163.68(10)°. The second carboxylate group of the ligand Thgl5? is not coordinated to the Ge atom. The coordination numbers of the cations K(1)+ and K(2)+ are seven and nine, respectively (K(1)-O, 2.685–2.889 Å; K(2)-O, 2.675–3.262 Å). In the crystal, the structural units are united into a three-dimensional framework.  相似文献   

8.
Thermogravimetry combined with evolved gas mass spectrometry has been used to characterise the mineral crandallite CaAl3(PO4)2(OH)5·(H2O) and to ascertain the thermal stability of this ‘cave’ mineral. X-ray diffraction proves the presence of the mineral and identifies the products of the thermal decomposition. The mineral crandallite is formed through the reaction of calcite with bat guano. Thermal analysis shows that the mineral starts to decompose through dehydration at low temperatures at around 139 °C and the dehydroxylation occurs over the temperature range 200–700 °C with loss of the OH units. The critical temperature for OH loss is around 416 °C and above this temperature the mineral structure is altered. Some minor loss of carbonate impurity occurs at 788 °C. This study shows the mineral is unstable above 139 °C. This temperature is well above the temperature in the caves of 15 °C maximum. A chemical reaction for the synthesis of crandallite is offered and the mechanism for the thermal decomposition is given.  相似文献   

9.
Sublimation of europium pivalate binuclear complexes Eu2(Piv)6 and [Eu2(Piv)6 · (Phen)2] (Piv = (CH3)3CCOO, Phen = C12H8N2) in the temperature range of 383–660 K is studied by the Knudsen effusion method with mass-spectrometric analysis of the gas phase. The vaporization of Eu2(Piv)6 is shown to be accompanied by polymerization and the formation of Eu2(Piv)6 and Eu4(Piv)12 molecules. The saturated vapor over the mixed-ligand complex of europium pivalate with o-phenanthroline consists of Phen, Eu2(Piv)6, and Eu4(Piv)12 molecules. The partial pressures of the gas components, as well as the standard enthalpies of sublimation and dissociation of the reaction proceeding with removal of phenanthroline have been determined.  相似文献   

10.
The crystal structure of a double complex salt of the composition [Au(en)2]2[Cu(C2O4)2]3·8H2O (en = ethylenediamine) at 150 K is determined by single crystal X-ray diffraction. The crystal data for C20H48Au2Cu3N8O32 are: a = 9.1761(3) Å, b = 16.9749(6) Å, c = 13.4475(5) Å, β = 104.333(1)°, V = 2029.43(12) Å3, P21/c space group, Z = 2, d x = 2.450 g/cm3. It is demonstrated that the thermal decomposition of the double complex salt in a helium or hydrogen atmosphere affords the solid solution Au0.4Cu0.6.  相似文献   

11.
[Ln(H2O)8][Cr(NCS)6] · 5H2O aqua complexes, where Ln = Er (1), Lu (2), have been found in an aqueous solution instead of binary complex salts with an organic ligand in their cation, when crystal products of the reaction between Ln(NO3)3 · 6H2O (Ln = Er, Lu), K3[Cr(NCS)6] · 4H2O, and 8-oxyquinoline (C9H7NO) were studied by X-ray diffraction. Crystals of complexes 1 and 2 are isostructural and crystallize in triclinic system, space group P\(\bar 1\), Z = 2. For complex 1: a = 9.0677(4) Å, b = 9.3115(4) Å, c = 16.9595 Å, α = 81.526(2)°, β = 86.153(2)°, γ = 83.879(2)°, V = 1406.33(10) Å3, ρcalc = 1.894 g/cm3; for complex 2: a = 9.0438(3) Å, b = 9.2880(3) Å, c = 16.9181(3) Å, α = 81.7250(10)°, β = 86.1600(10)°, γ = 83.8850(10)°, V = 1396.38(7) Å3, ρcalc = 1.926 g/cm3.  相似文献   

12.

Abstract  

Three novel lanthanide-organic frameworks: [Ln2(pyba)33-OH)22-OH)(H2O)] n (Ln = Er (1), Y (2), Dy (3) Hpyba = 4-pyridin-4-yl-benzoic acid) have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. Structure analysis shows that each {Ln43-OH)42-OH)2} cluster units interconnect to form 1-D chains, which are further linked by π–π interactions to make a 3-D supramolecular network structure. Furthermore, the IR, PXRD and TGA of compounds 13 were also studied.  相似文献   

13.
An individual crystalline compound Pb(UO2)2O2(OH)2·(H2O) was obtained by reaction of synthetic schoepite UO3·2.25H2O with an aqueous solution of lead(II) nitrate under hydrothermal conditions. The composition and structure of this compound were determined, and the processes of its dehydration and thermal decomposition were studied by chemical analysis, X-ray diffraction, IR spectroscopy, and thermography.  相似文献   

14.
A solvatothermal reaction of the octahedral cluster molybdenum complex (H3O)2[Mo63-Cl)8Cl6] · 6H2O with CaCl2 · 6H2O and OPPh3 in acetonitrile gave the known polymeric complex trans-[{Ca(OPPh3)4}{Mo63-Cl)8Cl6}]. However, a closer examination revealed that this system also produces a novel cluster complex, [Ca(OPPh3)5][Mo63-Cl)8Cl6] · OPPh3, which was isolated and characterized by X-ray diffraction.  相似文献   

15.
Syntheses and molecular structures of the heterometallic complexes of nickel cyclopentadienyl triphenylphosphine tellurophenolate with tungsten carbonyls (II and III) (CIF files CCDC nos. 1559733 and 1559734, respectively) are described.  相似文献   

16.
The [Co(DH)2(Py)2][H2F3] complex (DH? is the dimethylglyoxime residue) is synthesized and studied by X-ray diffraction analysis. Structural units of the crystal are complex cations [Co(DH)2(Py)2]+ and anions [H2F3]?. Two residues of α-dimethylglyoxime linked by intramolecular hydrogen bonds O-H?O lie in the equatorial plane of the octahedral Co(III) complex, and two pyridine molecules occupy the apical positions. The H2F 3 ? anion is formed due to the association of the F? ion with two HF molecules through hydrogen bonds F-H?F. Weak intermolecular interactions C-H?F and C-H?O are observed in the crystal. The problem of the influence of these interactions on the packing of the complexes in crystal is discussed.  相似文献   

17.
A new Co(III) complex of 1,2-cyclohexanedionedioxime and thiocarbamide with an SO 4 2? anion and solvation water molecules in the outer sphere has been synthesized and its structure has been defined. Orthorhombic crystals, a = 11.659(2) Å, b = 26.448(5) Å, c = 30.142(6) Å, V = 9295(3) Å 3, Z = 8, dcalc = 1.599 g/cm3, space group Pbca; final R index is 0.0578 for 8221 reflections with I > 2σ(I). In the octahedral Co(III) complex, two 1,2-cyclohexanedionedioxime residues lie in the equatorial plane, while two thiocarbamide molecules are in the axial plane. Intramolecular bonds: N-H…O and O-H…O type hydrogen bonds and π-π interactions that stabilize the complex cations. In crystal, the components are linked by N-H…O and O-H…O hydrogen bonds into a 3D framework.  相似文献   

18.
Triethylamine reacts with aqueous zinc acetate and the product of its thermolysis in the presence of benzoic acid to yield the complexes [Zn74-O)(μ-OOCMe)10][η-OC(Me)OHNEt3]2 (1) and [Zn2(μOOCPh)4][η-OC(Me)OHNEt3]2 (2), respectively. The reactions of 1 and 2 with 3,5-dimethylpyrazole at room temperature in benzene yield pyrazolate-bridged binuclear complexes Zn2(μdmpz)2(Hdmpz)2(OOCR)2 (R = Me (3), Ph (4)). The structures of complexes 1–4 have been determined by X-ray crystallography.  相似文献   

19.
The cationic networks that fix the distribution of cations in planar sections parallel to basis planes of the unit cell of crystal structures have been studied. Topologically identical cationic networks have been shown to be the carriers of deep structure-forming “memory” that successively relates the structures of rare earth metals (La ST) and oxides Ln2O3 (A-and B-Ln2O3 ST) to the structures of double condensed phosphates MLn(PO3)4 and MLnP4O12.  相似文献   

20.
The clathrate [Zn(C6H5COO)2(H2O)2] · 2CH3COOH (I) was obtained for the first time from zinc(II) benzoate. The individuality, the unit cell parameters, and the number of “guest” molecules in complex I were determined from X-ray diffraction and derivatographic data. Its crystal structure was solved.  相似文献   

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