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1.
1 INTRODUCTION The design and synthesis of polynuclear com- plexes have attracted chemists?attention in the contemporary chemistry, since their clusters maybe lead to novel materials with magnetic, optical, electronic and catalytic properties of the constituent metals[1~3]. It is also prevalently interesting to synthesize high-nuclearity metal complexes for their nanoscopic dimensions[3, 4]. Spectroscopic properties of the lanthanides are widely used in the study of biological systems. …  相似文献   

2.
The reaction of Eu metal with HOPr(i)/toluene solutions yielded the mixed Eu(2+)/Eu(3+) alkoxide [Eu(4)(OPr(i))(10)(HOPr(i))(3)] x 2HOPr(i) (1), in contrast to the other lanthanide metals, which exclusively yield trivalent lanthanide ions in the alkoxides formed. Metathesis between EuCl(3) and 3KOPr(i) and stoichiometric hydrolysis yielded the square-pyramidal Eu(5)O(OPr(i))(13) (2), and metathesis with EuCl(3) and 3KAl(OPr(i))(4) gave EuAl(3)(OPr(i))(12) (3). The structures of these compounds were determined by single-crystal X-ray diffraction. IR spectroscopic studies showed that the solid-state molecular structure of the three alkoxides remained close to intact in solution. Further characterizations were made with UV-vis spectroscopy, differential scanning calorimetry, and solubility studies. It was also found that 1 can be converted to 2 by oxidation with dioxygen, but 2 was not reduced by Eu metal to 1. The reactions of 2 and 1 with Al(4)(OPr(i))(12) in toluene/HOPr(i) solvent were studied by IR and UV-vis spectroscopy; 2 reacted completely to form 3 in 2 h at 75 degrees C, while 1 reacted to yield 3 and other unidentified Eu(2+) containing product(s) in the same time.  相似文献   

3.
The mechanochemical synthesis offers an easy access to obtain alkaline earth metal terephthalates M(C8H4O4) · nH2O (M = Ca, Sr, Ba). In the presented study we describe for the first time the mechanochemical synthesis of powders of Ca(C8H4O4) · 3H2O, Ca(C8H4O4), Sr(C8H4O4) · H2O, and Ba(C8H4O4), which so far were only synthesized as single crystals from aqueous solutions or by reactions in an autoclave. Furthermore, a new hydrate Ba(C8H4O4) · 2(1.5)H2O, not described so far in the literature, was prepared. All compounds were characterized by X‐ray powder diffraction, thermal analysis, elemental analysis, FT‐IR, and MAS NMR spectroscopic measurements.  相似文献   

4.
Na5[CuO2](OH)2 has been obtained as orange single crystals from mixtures of NaOH, Na2O and Cu2O in sealed Ag containers. The crystal structure has been refined from X‐ray diffraction data (IPDS data, Pnma, Z = 4, a = 607.4(1) pm, b = 891.2(1) pm, c = 1201.0(2) pm, R1 = 0.03). The characteristic unit is the bent [CuO2]3– complex (∠(O–Cu–O) = 170°). The reactivity of Na5[CuO2](OH)2 has been studied by DSC and in situ X‐ray diffraction techniques. IR spectroscopy has been used for further characterization. The Madelung Part of the Lattice Energy (MAPLE) has been calculated as well.  相似文献   

5.
In alkali metal and lanthanide coordination chemistry, triphenylsiloxides seem to be unduly underappreciated ligands. This is as surprising as that such substituents play a crucial role, among others, in stabilizing rare oxidation states of lanthanide ions, taking a part of intramolecular and molecular interactions stabilizing metal-oxygen cores and many others. This paper reports the synthesis and characterization of new lithium [Li4(OSiPh3)4(THF)2] (1), and sodium [Na4(OSiPh3)4] (2) species, which were later used in obtaining novel gadolinium [Gd(OSiPh3)3(THF)3]·THF (3), and erbium [Er(OSiPh3)3(THF)3]·THF (4) configuration, it can result in res were determined for all 1–4 compounds, and in addition, IR, Raman, absorption spectroscopy studies were conducted for 3 and 4 lanthanide compounds. Furthermore, direct current (dc) variable-temperature magnetic susceptibility measurements on polycrystalline samples of 3 and 4 were carried out in the temperature range 1.8–300 K. The 3 shows behavior characteristics for the paramagnetism of the Gd3+ ion. In contrast, the magnetic properties of 4 are dominated by the crystal field effect on the Er3+ ion, masking the magnetic interaction between magnetic centers of neighboring molecules.  相似文献   

6.

Chemical preparation, crystal structure, thermogravimetric and differential analysis, solid state 31P MAS NMR characterization, and IR spectroscopic investigations are given for a new organic cation dihydrogenmonophosphate, (2-CH3OC6H4CH2NH3)H2PO4. This compound is monoclinic C2/c, with unit cell parameters a = 27.740(8), b = 4.827(2), c = 16.435(3) Å, β = 93.79(2)°, V = 2196 (1) Å3, Z = 8, and ρ = 1.422 g · cm?3. The crystal structure has been determined and refined to R = 0.046 (Rw = 0.056), using 1,746 independent reflections with I > 3σ (I). Its atomic arrangement can be described by infinite polyanions [H2PO4] n n ?, organized in ribbons alternating with organic cations. Strong hydrogen bonds connect the different components. Electrical conductivity measurements show that the [2-CH3OC6H4CH2NH3]H2PO4 has a low ionic conductivity value at 403 K.  相似文献   

7.
A novel mixed ligand nickel complex [NiLB] [H2L-N-4-diethylaminosalicylidine-N′-4-nitrobenzoyl hydrazone and B-4-picoline] has been synthesized and characterized by elemental analysis, IR spectrum, UV-Vis spectrum and structure has been confirmed by single crystal X-ray structure analysis. The crystal structure reveals that the complex adopts distorted square planar structure with ONO donor atoms of primary ligand and N donor atom of the secondary ligand 4-picoline.  相似文献   

8.
The new polyoxovanadate (POV) compound {[Cu(H2O)(C5H14N2)2]2[V16O38(Cl)]} · 4(C5H16N2) was synthesized under solvothermal conditions and crystallizes in the tetragonal space group I41/amd with a = 13.8679(6), c = 45.558(2) Å, V = 8761.7(7) Å3. The central structural motif is a {V16O38(Cl)} cluster constructed by condensation of 16 square‐pyramidal VO5 polyhedra. The cluster hosts a central Cl anion. According to valence bond sum calculations, chemical analysis and magnetic properties the cluster anion may be formulated as [V15IVVVO38(Cl)]12–, i.e., only one vanadium atom is not reduced. To the best of our knowledge this is the first reported {V16O38(X)} cluster in this VIV:VV ratio. The presence of the two different vanadium oxidation states is clearly seen in the IR spectrum. An unusual and hitherto never observed structural feature is the binding mode between the [Cu(H2O)(C5H14N2)2]2+ complexes and the [V15IVVVO38(Cl)]12– anion. The Cu2+ ion binds to a μ2‐O atom of the cluster anion whereas in all other transition metal complex‐augmented POVs bonding between the transition metal cation and the anion occurs through terminal oxygen atoms of the POV. The magnetic properties are dominated by strong antiferromagnetic exchange interactions between the V4+ d1 centers, whereas the Cu2+ d9 cations are magnetically decoupled from the cluster anion. Upon heating, the title compound decomposes in a complex fashion.  相似文献   

9.
Abstract

A new adduct 3-ammoniumphenyl sulfone dihydrogenphosphate phosphoric acid, [C12H14N2O2S](H2PO4)2H3PO4, has been synthesized by slow evaporation at room temperature using 3-aminophenyl sulfone as the structure-directing agent. The structure, determined by single-crystal X-ray diffraction at 293 K, can be described as inorganic layers built by H2PO4 ? groups and H3PO4 molecules, parallel to the (a, c) planes at y = 0.5, between which molecules of the organic group [C12H14N2O2S]2+ are inserted. In this atomic arrangement, hydrogen bonds and van der Waals interactions between the different species play an important role in the tri-dimensional network cohesion. Solid-state 13C and 31P MAS NMR spectroscopies are in agreement with the X-ray structure.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Tables S1 and S2. Figures S1 and S2.]

GRAPHICAL ABSTRACT   相似文献   

10.
Abstract

Sodium copper (II) arsenate Na7Cu4(AsO4)5 has been grown by conventional high-temperature, solid-state methods in molten-salt media. It was characterized by single crystal X-ray diffraction (XRD), thermal analysis (DTA–TGA), scanning electron microscopy (SEM), semiquantitative energy dispersive spectroscopy analysis (EDS), and vibrational spectroscopy. Na7Cu4(AsO4)5 exhibits a three-dimensional framework built up of CuO5, CuO4, and AsO4 polyhedra, with intersecting channels in which the Na+ cations are located. The three-dimensional cohesion of the framework results from Cu–O–As bridges. CuO5 and CuO4 polyhedra are elongated due to the Jahn–Teller effect, whereas AsO4 tetrahedra are almost regular. This new structural model is validated by the charge distribution (CD) analysis. The infrared and Raman spectra confirmed the presence of AsO4 tetrahedra.

[Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional tables and figures.]  相似文献   

11.
本文报道了双金属离子对配合物 [Mo(dtc) 4 ] [Er(dtc) 4 ] (dtc,N、N-二乙基氨基二硫代甲酸根 )的合成 ,并用四圆 X-射线衍射仪测定了配合物的晶体结构 ,同时对配合物的性质进行了较为详细的报道。  相似文献   

12.
13.
The reaction of Et4NCl, C6H5SeNa and W(CO)6 in MeCN afforded a new dinuclear tungsten(Ⅰ) complex W2(SePh)2(CO)6(MeCN)2 1 (Mr = 929.98). The crystal structure has been determined by X-ray single-crystal diffraction. 1 Crystallizes in monoclinic, space group P21/n with a = 7.501(1), b = 18.387(2), c = 9.491(1) (A), β = 103.897(2)°, V = 1270.6(3) (A)3, Z = 2, Dc = 2.431g/cm3, μ = 119.50 cm-1, F(000) = 852, R = 0.0695 and wR = 0.1724 for 2220 independent reflections with I > 2σ(Ⅰ). The X-ray structure analysis reveals that the W2Se2 core of 1 is planar with W-W bond length of 3.0433(13) (A) and W-Se of 2.5922(17) (A).  相似文献   

14.
The synthesis, X-ray crystal structure, thermal properties and electrochemistry of the new complex formulated as {Er(DMSO)7}PW12O40 are reported. The single-crystal X-ray analysis reveals that the crystal crystallizes in the monoclinic system, space group P21/c with a = 11.767(2), b = 14.909(3), c = 34.905(7) , β = 98.97(3)°, Mr = 3591.33, V = 6049(2) 3, Dc = 3.944 g/cm3, Z = 4, GOOF = 1.098, F(000) = 6340, R = 0.0490 and wR = 0.1202. Crystal structure analysis indicates that the Er(Ⅲ) is seven-coordinate with a distorted pentagonal bipyramid and combines to the anion [PW12O40]3- via static electric force.  相似文献   

15.
The aquaorotatotriethanolaminenickel(II) monohydrate, [Ni(HOr)(H2O)(tea)]·H2O ( 1 ), was synthesized and characterized by means of elementel analysis, IR and UV‐Vis, spectroscopy, magnetic susceptibility, thermal analysis and X‐ray diffraction techniques. The nickel ion in [Ni(C5H2N2O4)(H2O)(N(C2H4OH)3)] is chelated to the deprotonated N3 pyrimidine atom and to the carboxylate oxygen atom of the bidentate orotate dianion, and to the one nitrogen and two oxygen atoms of the tridentate triethanolamine molecule and its octahedral geometry is completed by an aqua ligand. It crystallizes in the monoclinic system, space group P21/c with lattice parameters a = 7.1528(5) Å, b = 19.4903(14) Å, c = 11.8085(8) Å, β = 106.237(5)°, V = 1580.55(19) Å3, Z = 4. An extensive three dimensional network of Ow‐H…O, N‐H…O and O‐H…O hydrogen bonds, π‐π and π‐ring interactions are responsible for crystal stabilization. The decomposition reaction take places in the temperature range 20‐1000 °C in the static air atmosphere. Thermal decomposition of 1 proceeds in three stages.  相似文献   

16.
Veith M  Mathur S  Huch V 《Inorganic chemistry》1996,35(25):7295-7303
Metathesis reactions between CdI(2) and KM(2)(OPr(i))(9) (M = Ti, Hf) in toluene produce monomeric iodo-heterobimetallic isopropoxides ICdM(2)(OPr(i))(9) (1, M = Ti; 2, M = Hf) which have been characterized by solution ((1)H, (13)C, and (113)Cd) and solid state ((13)C and (113)Cd) CP MAS NMR spectroscopy, microanalysis, cryoscopic molecular weight determination, and single crystal X-ray diffraction study. Both 1 and 2 in the solid state represent the first structurally characterized examples of halide heterobimetallic alkoxides based on {Ti(2)(OPr(i))(9)}(-) and {Hf(2)(OPr(i))(9)}(-) bioctahedral subunits, respectively. The overall molecular geometry of 1 and 2 can be viewed formally as an interaction of the CdI(+) fragment with {M(2)(OPr(i))(9)}(-) substructures via two terminal and two bridging (&mgr;(2)-) isopropoxy groups. Reaction of 1 and 2 with equimolar KBa(OPr(i))(3) in toluene afforded novel heterotermetallic isopropoxides [{Cd(OPr(i))(3)}Ba{M(2)(OPr(i))(9)}](2) (3, M = Ti; 4, M = Hf). Formation of heterotermetallic frameworks involves an interesting rearrangement of the central metal atoms between the two precursor molecules, which is probably commanded by the tendency of barium to achieve higher coordination numbers. The dimeric forms of 3 and 4 as shown by cryoscopy and (113)Cd solution and solid state CP MAS NMR studies are confirmed by crystallography. The X-ray crystal structures of 3 and 4 reveal, as a common feature, a central Ba(&mgr;(2)-OPr(i))(2)Cd(&mgr;(2)-OPr(i))(2)Cd(&mgr;(2)-OPr(i))(2)Ba unit formed by a spirocyclic linking of two LBa(OPr(i))(2) (3, L = Ti(2)(OPr(i))(9); 4, L = Hf(2)(OPr(i))(9)) units to a four membered, Cd(2)(OPr(i))(2), ring. Crystal data: for 1, monoclinic, space group P2(1)/m, a = 11.71(2) ?, b = 15.78(3) ?, c = 12.16(2) ?, beta = 116.69(14) degrees, Z = 2; for 2, triclinic, space group P&onemacr;, a = 9.825(2) ?, b = 11.428 ?, c = 20.619 ?, alpha = 95.619(12) degrees, beta = 99.915(11) degrees, gamma = 111.347(11) degrees, Z = 2; for 3, monoclinic, space group P2(1)/c, a = 22.68(2) ?, b = 12.603(11) ?, c = 19.00(2) ?, beta = 96.83(8) degrees, Z = 2; for 4, monoclinic, space group P2(1)/c, a = 23.197(5) ?, b = 12.886(3) ?, c = 19.378(4) ?, beta = 97.18(3) degrees, Z = 2.  相似文献   

17.
The synthesis, structure and properties of Na2Zn(OEt)4(HOEt)5, having the right Na:Zn ratio for sol–gel synthesis of the highly Na-ion conducting ceramic Na1.8Zn0.9Si1.1O4, is described. It was synthesised in high yield by a metathesis reaction of ZnCl2 and 4NaOEt in ethanol or ethanol/toluene solvent. The structure was determined by single-crystal X-ray methods and consists of two symmetry related polymeric strands with the metal sequence ...–Zn–Na–Na–Zn–.... Extensive hydrogen bonding is present within each chain. Further characterization was made with IR- and Raman-spectroscopy and thermo-calorimetry, showing that the compound is stable to 65°C.  相似文献   

18.
1INTRODUCTIONThephysiologicaleffectofrareearthionshasarousedgreatattentionrecent-lya'"-Aminoacids,assmallbio-moleculeswithspeialfunctions,existinplasmainhighconcentrations(3),sothestudyontheinteractionsbetweenrareearthionsandaminoacidsmayshedsomelightsonthephysiologicaleffectofrareearthsion.Inthepastfewyears,about4orareearthcomplexeswithaminoacidswereStructurallycharacterndt'3.Amongthemsevenaretheprolinecomplexes.Intheseprolinecom.plexes,molarratioofmetal(M)andproline(L)M:L=1:1complexis…  相似文献   

19.
20.
A novel complex {Cu(Bobb)2](pic)2}2 [pic = picrate anion, Bobb = 1,3‐bis(1‐benzylbenzimidazol‐2‐yl)‐2‐oxopropane] was synthesized and characterized by means of elemental analyses and electrical conductivity. The crystal structure of the copper complex has been determined by single‐crystal X‐ray diffraction. A study of the electrochemistry of the title compound was carried out by using cyclic voltammetry. It revealed that the copper complex exhibits a quasi‐reversible redox process. The X‐ray structure of the above complex shows that the unit cell consists of two centrosymmetric, crystallographically independent molecules, in which the copper(II) ions have the same coordination environment and should be described as distorted octahedron. The complex is formed of { ··· Cu(2) ··· Cu(1) ··· Cu(1) ··· } supramolecular configuration by π ··· π stacking interactions between the benzimidazole rings. The complex was also identified by IR and electronic spectroscopy.  相似文献   

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