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1.
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   

2.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.

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   

8.
The compound [Co(NH3)6]2[W4Se4(CN)12]·8.5H2O was obtained by evaporating an aqueous ammonia solution of K6[W4Se4(CN)12]·6H2O and CoCl2·6H2O complexes. The starting Co(II) of CoCl2·6H2O transforms into [Co(NH3)6]3+ when exposed to air in a water-ammonia medium. Crystal data: triclinic crystal system, a = 10.7750(8) Å, b = 12.2843(9) Å, c = 19.6539(14) Å; α = 90.213(2)°, β = 99.910(2)°, γ = 114.737(1)°, V = 2319.1(3) Å3, space group , Z = 2, D x = 2.633 g/cm3.Original Russian Text Copyright © 2004 by I. V. Kalinina, Z. A. Starikova, F. M. Dolgushin, D. G. Samsonenko, and V. P. Fedin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 905–908, September–October, 2004.  相似文献   

9.
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   

10.
The structure of [Pb3(OH)4Co(NO2)3](NO3)(NO2)·2H2O is determined by single crystal X-ray diffraction. The crystallographic characteristics are as follows: a = 8.9414(4) Å, b = 14.5330(5) Å, c = 24.9383(9) Å, V = 3240.6(2) Å3, space group Pbca, Z = 8. The Co(III) atoms have a slightly distorted octahedral coordination formed by three nitrogen atoms belonging to nitro groups (Co–Nav is 1.91 Å) and three oxygen atoms belonging to hydroxyl groups (Co–Oav is 1.93 Å). The hydroxyl groups act as μ3-bridges between the metal atoms. The geometric characteristics are analyzed and the packing motif is determined.  相似文献   

11.
The complex Na3(NH4)2[Ir(SO3)2Cl4]·4H2O was examined with single crystal X-ray diffraction and IR spectroscopy. Crystal data: a = 7.3144(4) Å, b = 10.0698(5) Å, c = 12.3748(6) Å, β = 106.203(1)°, V = 875.26(8) Å3, space group P21/c, Z = 2, d calc = 2.547 g/cm3. In the complex anion two trans SO 3 2? groups are coordinated to iridium through the S atom. The splitting of O-H bending vibrations of crystallization water molecules and N-H ones of the ammonium cation is considered in the context of different types of interactions with the closest neighbors in the structure.  相似文献   

12.
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   

13.
Aqueous solutions of La(CH3CO2)3, NaCH3CO2 and La(ClO4)3 were studied using Raman spectroscopy. In dilute NaCH3CO2 solution, acetate is fully hydrated and forms only minor amounts of ion pairs. The characteristic Raman bands are discussed and assigned. In fairly dilute La(ClO4)3 solutions, the La3+(aq) ion occurs as the nonahydrate. The separation of the carboxylate bands, νas – νs (Δ-value), in NaCH3CO2(cr) compared to La(CH3CO2)3·1.5H2O(cr) correlates with the bonding type of acetate which is “ionic” in the former but bidentate chelating/tridentate chelating in the latter. Other acetate bands such as the deformation mode of the CO2 moiety, δ CO2, and the two rocking vibrations (ρ), as well as the C–C stretch show marked differences in their band positions in NaCH3CO2(cr) compared to the ones in La(CH3CO2)3·1.5H2O(aq). In a ternary solution of La(CH3CO2)3/LaCl3 with a molar ratio La3+(aq): \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \)(aq) = 3.87: 1.00), the bands of the bound acetate on La3+ were characterized and compared to those of fully hydrated acetate, \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \left( {\text{aq}} \right) \). In this solution, almost all acetate is ligated to La3+ in a bidentate fashion and two complex species could be identified (molar ratios La3+: \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \)  = 1:1 and 1:2, respectively). In La(CH3CO2)3 solutions in H2O and D2O strong acetato complexes are formed and the bands of the bound acetate were characterized and compared with the ones of the fully hydrated acetate modes. A dilution series down to 0.0037 mol·L?1 in La(CH3CO2)3(aq) and to 0.0150 mol·L?1 in La(CH3CO2)3(D2O) showed that two acetate complexes are formed in these solutions. Again, it was shown that in these solutions the bound acetates on La3+ exist as bidentate ligands. DFT frequencies of the acetate on clusters {La(OH2)7O2CCH3)}2+ and {La(OH2)5(O2CCH3)2}+ compared well with the measured values. By determining the ligation number, \( \bar{n} \), it can be established that in dilute solutions, below 0.04 mol·L?1, a complex with a 1:1 stoichiometry (La3+: \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \)) exists in equilibrium with “free” acetate while in more concentrated solutions a 1:2 complex also forms. La3+(aq) hydrolysis is slight and very small equilibrium concentrations of CH3COOH were detected (C–C stretch at 893 cm?1). From quantitative Raman measurements, K 1 was determined to be 160 ± 10 at 22 °C.  相似文献   

14.
The title compound, cobalt 4′,7-diethoxylisoflavone-3′-sulfonate([Co(H2O)6](X)2⋅8H2O, X = C19H17O4SO3) was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic space group P-1 with cell parameters a = 9.026(3) Å, b = 16.431(5) Å, c = 18.195(6) Å, α = 72.289(4), β = 87.498(4), γ = 82.775(5), V = 2550.1(13) Å−3, Dc = 1.419 Mg m−3, and Z = 2. The results show that the title compound consists of one cobalt cation, six coordinated water molecules, eight lattice water molecules, and two 4′,7-diethoxylisoflavone-3′-sulfonate anions, C19H17O4SO3. Two anions have different conformations. Twelve H atoms of six coordinated water molecules, as donors, form hydrogen bonds with four oxygen atoms of sulfo-groups of two anions and eight oxygen atoms of eight lattice water molecules. In addition, π < eqid1 > ⋅ < eqid2 > π stacking interactions exist in the crystal structure, which together with hydrogen bonds lead to supramolecular formation with a three-dimensional network.  相似文献   

15.
The structure of the salt Cs[Gd(H2O)4Re6Te8(CN)6]·4H2O (space group P-1, a = 9.436(5) Å, b = 12.365(7) Å, c = 15.187(8)Å, α = 89.104(10)°, β = 86.996(10)°, γ = 82.304(9)°) has been established by single crystal XRD. The structure of the compound features layers involving Gd3+ cations bound to cluster anions [Re6Te8(CN)6]4? through cyanide groups. The interlayer space contains cesium cations and crystallization water molecules.  相似文献   

16.
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   

17.
A new dichromium(III) cobalt(II) diphosphate(V) of the formula CoCr2(P2O7)2 was detected in the Co3Cr4(PO4)6–Cr(PO3)3 system. The new compound was obtained as a result of high-temperature solid-state reactions between CoCO3, Cr2O3 and (NH4)2HPO4 as well as between Cr(PO3)3 and Co3Cr4(PO4)6. CoCr2(P2O7)2 was characterized using XRD, DTA and IR methods. Results demonstrated that CoCr2(P2O7)2 crystallizes in the triclinic system and its unit cell parameters were calculated. Its infrared spectrum was presented. CoCr2(P2O7)2 melts incongruently at 1270±10 °C with a formation of solid α-CrPO4. The compound Co3Cr4(PO4)6, component of the system under study, was obtained for the first time as a pure phase. Its thermal stability was also investigated. Co3Cr4(PO4)6 is stable in air up to 1410 ± 20 °C.  相似文献   

18.
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   

19.
A method for the synthesis of potassium pivalates (trimethylacetates) from potassium tert-butoxide and pivalic acid was proposed. The complexes of the formulas [K(H2O)(Piv)](I) and [K2(Phen)(H2O)2(Piv)2] (II) (Piv denotes the pivalate anion and Phen denotes 1,10-phenanthroline) were obtained and characterized by elemental analysis and IR and 1H NMR spectroscopy. The crystal structures of complexes I and II were determined using X-ray diffraction. Crystal structure I has a layered motif with two nonequivalent K atoms (C.N.s 5 + 2 and 6). The coordination of phenanthroline in II gives rise to a ribbon motif, the structure containing three nonequivalent K atoms (C.N.s 6, 6 + 1, and 8).  相似文献   

20.
Synthesis, X-ray diffraction, IR and luminescence spectroscopic studies of the monohydrate of pentachloroantimonate(III) of doubly protonated ciprofloxacin (C17H19N3O3F)SbCl5 · H2O (I) were performed. The structure of I is formed by SbCl6 octahedra combined into polymeric chains [SbCl5] n 2n? through common vertices, ciprofloxacinium cations (CfH3)2+, and water molecules linked by hydrogen bonds. CfH is protonated at the carbonyl oxygen atom and the terminal nitrogen atom of the piperazinyl group. The electronic and geometric aspects determining the luminescence properties of I and of related compounds are discussed.  相似文献   

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