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1.
1 INTRODUCTION Polyoxomolybdates have been of great interest due to their unique structural varieties, associated multitude of properties and applications as catalysis, medicine and material[1, 2]. One of the most impor- tant aspects is the synthesis and investigation of the materials on polyoxomolybdates containing organo- metallic groups[3~5]. Such materials can provide molecular models for heterogeneous catalysis and display cooperative effects or bifunctional catalytic activity[6]. O…  相似文献   

2.
The title compound K3[HO{VO(O2)2}2]·H2O has been synthesized and its crystal structure was determined by X-ray diffraction method. The crystal is of monoclinic, space group P21/c with a = 6.7078(3), b = 9.9539(6), c = 15.8182(9)A, β = 93.702(3)0, V = 1053.96(10)A3, Mr = 414.20, Dc = 2.610 g/cm3, Z = 4, λ(MoKα) = 0.71073A, F(000) = 808, μ = 3.014 mm-1, the final R = 0.0173 and wR = 0.0466 for 2178 observed reflections with I > 2σ(I). X-ray diffraction reveals that the coordination polyhedra of V atoms are not chemically equivalent: the V(1) and V(2) polyhedra can be described as pentagonal pyramid and pentagonal bipyramid, respectively.  相似文献   

3.
The crystal structure of the complex (NH4)2[UO2(MoO4)2] · H2O is determined. The unit cell parameters are a= 7.916, b= 10.885, c= 13.476 Å, = 98.40°, V= 1148.8 Å3, space group P21/c, Z= 4, (calcd) = 3.452 g/cm3, R= 0.0406, R w= 0.0850. The coordination polyhedron of the uranium atom is a pentagonal bipyramid with its equatorial plane formed by oxygen atoms of five MoO4groups.  相似文献   

4.
1 INTRODUCTION Though the investigation on chemistry of tran- sition metal-peroxy complexes has been extensively carried out, up to now, only four structures of purely inorganic dimeric peroxovanadates have been deter- mined by single-crystal X-ray meth…  相似文献   

5.
The title compound Na5H37P6Mo18O90 1 (Mr=1658) was synthesized under hydrothermal condition and its crystal structure was determined by X-ray diffraction. It crystallized in the monoclinic system, space group P21 with a =14.957(1), b =16.535(1), c = 16.159(1)?,β=108.586(2)°, V=3787.85?3, Dc =3.040g/cm3, Z=2,μ(MoKα)=3.17mm-1, F(000)=3242. The final R and wR are 0.0500 and 0.1535 for 6643 observable reflections with I≥2σ(I), respectively. The result of structure analysis indicates that [Na(HPO4)2(PO4)4-Mo18 O49]5-anions 2 in 1 has the symmetry of C2V, in which each MoVIO6 octahedron is connected to adjacent PO4 tetrahedra through corner-sharing and to adjacent octahedra through edge-sharing or corner-sharing.  相似文献   

6.
A new complex [Zn(OH2)(HDPA)2]·3H2O 1 (H2DPA = 2,6-pyridine-dicarboxylic acid) has been prepared at room temperature from the reaction of zinc(II) chloride and 2,6-pyri- dine-dicarboxylic acid in mixed solvent of H2O and EtOH with pyridine, and characterized by X-ray analysis and thermal analysis, exhibiting that the coordination geometry of Zn(II) ion is an octa- hedron. Crystal data: ZnC14H16N2O12, Mr = 469.66, monoclinic, P21/n, a = 7.0067(3), b = 23.8215 (12), c = 10.7404(3)(A), β = 99.823(2)°,V = 1766.40(13)(A)3, Z = 4, Dc = 1.766 g/cm3, F(000) = 960, μ = 1.463 mm-1, R1 = 0.0462 and wR2 = 0.0884 (I > 2σ(I)).  相似文献   

7.
1 INTRODUCTION Nitronyl nitroxide radicals (NITR), stable organic radicals, have played an important role in the design and synthesis of molecular magnetic materials[1, 2]. However, nitronyl nitroxide radicals are poor elec- tron-donor ligands and their coordination ability is limited. Recently, it has led to the development of functionalized nitronyl nitroxide radicals in which a strong coligand is incorporated. Due to the strong coordinate ability of nitrogen atom from pryidinyl ring,…  相似文献   

8.
The title compound {Cu2(pdc)2(4,4′-bipy)(H2O)(3H2O}2 1 (H2pdc = pyridine-2,6- dicarboxylic acid, also known as dipicolinic acid; 4,4′-bipy = 4,4′-bipyridine) has been synthesized by the hydrothermal reaction and its structure was determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pī with a = 7.2278(3), b = 10.6259(4), c = 17.7614(6)A, α= 79.5990(10), β = 83.6300(10), γ = 71.8280(10)o, V = 1272.60(8)A3, C48H44Cu4N8O24, Mr = 1371.07, Z = 1, Dc = 1.789 g/cm3, μ = 1.747 mm-1, F(000) = 696, R = 0.0397 and wR = 0.1137 for 3938 observed reflections (I > 2σ(I)). There are two kinds of Cu coordination environments, and each central copper(II) atom is five-coordinated in a distorted square-based pyramidal coordination geo- metry. Four copper(II) atoms are linked by four pdc and two 4,4′-bipy ligands to form an annular rectangle structure. Extensive hydrogen-bonding interactions involving carboxylate O atoms as well as coordinated and free water molecules lead to the formation of a three-dimensional network struc- ture.  相似文献   

9.
A new mononuclear Co(Ⅱ) complex, [Co(hmz)2(H2O)4]·2H2O, has been synthesized by the reaction of Co(CH3COO)2·4H2O with 1-(4-hydroxyphenyl)-5-mercaptotetrazole (Hhmz). It crystallizes in the monoclinic system, space group P21/n with a = 13.502(5), b = 6.718(3), c = 13.972(6) (A), β = 117.532(4)°, V = 1123.9(8) (A)3, Z = 2, M r = 553.45, F(000) = 570, Dc = 1.635 g/cm3, μ = 1.008 mm-1, the final R = 0.0272 and wR = 0.0684 for 2194 observed reflections (Ⅰ> 2σ(Ⅰ)). The Co(Ⅱ) is six-coordinated by two nitrogen atoms from two hmz-1 ligands and four water molecules, forming an octahedral geometry. The intermolecular hydrogen bonding and offset-panel π-π stacking interactions between the adjacent molecules extend the compound into a three- dimensional supramolecular framework. The title compound emits strong blue fluorescent light (λem(max) = 427 nm) at room temperature and is red-shifted compared with free ligand Hhmz (λem(max) = 342 nm).  相似文献   

10.
A novel heterometallic complex [Na2Cu2Gd2(pdc)4(H2O)14·2H2O] (H3pdc = 1H- pyrazole-3,5-dicarboxylic acid) has been synthesized and characterized by 1R spectra, elemental analysis, and single-crystal X-ray analysis. The crystal belongs to the monoclinic system, space group P2 1/c with a = 7.9521(18), b = 12.251(3), c = 22.293(5) A, β = 110.173(5)°, V= 2038.5(8) A^3, Mr = 1388.13, Z = 2, F(000) = 1352, Dc = 2.261 g/cm^3,/2 = 4.380 mm^-1, the final R = 0.0409 and wR = 0.0622 for 2453 observed reflections with I 〉 2σ(I). The structural analysis shows that the Na^I, Cu^II and Gd^II ions are linked together by two kinds of bridging ligands (pdc^3- and H2O) to form a main moiety [Na2Cu2Gd2(pdc)4(H2O)14], which can be regarded as a centrosymmetric dimmer of [NaCuGd(pdc)2(H2O)7]. Many hydrogen bonds exist in the complex to build a 3D supramolecular framework.  相似文献   

11.
A novel coordination polymer [{Cd(hmbdc)(H2O)3}·2H2O]n (hmbdc=5-hydroxy- isophthalic acid) has been synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c, with a=9.599(3), b=18.699(5), c=7.557(2) (A), β= 108.198(4)°, V=1288.6(6) (A)3, Z=4, Mr=382.60, Dc=1.972 g/cm3, F(000)=760, μ=1.740, the final R=0.0555 and wR=0.0995 for 1732 observed reflections with Ⅰ > 2σ(Ⅰ). The structural analysis shows that the intermolecular hydrogen bonds and π-π interactions result in a three-dimensional supramolecular framework.  相似文献   

12.
A one-dimensional bimetallic compound {[CuCd(pba)(H2O)3]·2H2O}n in which pba was propylenebis (oxamic acid), was prepared. Crystal structure of the title compound was determined. It belongs to orthorhombic system, molecular formula CuCdC7H16N2O11, Mr=480.17, space group Pnma(#62), a=12.953(2), b=21.626(6), c=5.253(3)(A), V=1471(2)(A)3 and Dx=2.17g/cm3 for Z=4. The structure was solved by direct methods with final R=0.052 and Rw=0.063 for 1055 observed reflections with I>3σ(I). Two nitrogen atoms and two oxygen atoms from the oxamide and a water molecule coordinated to the CuII ion forming a square pyramidal geometry. Four oxygen atoms from the oxamide and two water molecules coordinated to the CdII ion forming an elongated octahedral geometry.  相似文献   

13.
The novel coordination polymer [Pr(BYBA)3(H2O)2]·[Pr(BYBA)3(H2O)] (BYBAH = 2-benzoylbenzoic acid) was yielded by hydrothermal synthesis, determined by single-crystal X-ray diffraction, and characterized by FT-IR and UV-Vis spectra. The crystal crystallizes in the triclinic system, space group P with a = 9.112(3), b = 14.644(5), c = 27.076(11) (A), α = 84.223(3), β = 87.816(4), γ = 88.902(4)o, V = 3592(2) (A)3, C84H60O21Pr2, Mr = 1687.14, Z = 2, F(000) = 1700, Dc = 1.560 g/cm3, μ = 1.419 mm-1, the final R = 0.0485 and wR = 0.1258 for 13035 observed reflections with I>2((I). The compound contains two different building units, [Pr2(BYBA)6(H2O)4] and [Pr2(BYBA)6(H2O)2]. It is noticeable that [Pr2(BYBA)6(H2O)4] is an isolated binuclear building block, in which the Pr3 ion centers are both located in an eight-coordinated environment. However, in [Pr2(BYBA)6(H2O)2] the Pr3 ion centers are located in a nine-coordinated environment and connected by BYBA ligands to form 1D chains.  相似文献   

14.
(1.10-Phenanthroline)-tris(4-amidobenzoate)dysprosium, [Dy(p-ABA)3Phen · H2O] · 1.5H2O (where p-ABA = p-amidobenzoate and Phen = 1.10-phenanthroline) has been synthesized. The complex was characterized by elemental analysis, UV, IR spectroscopy, and molar conductance. The crystal structure was determined by X-ray crystallography. The coordination number of the mononuclear complex is nine. The crystals are triclinic, space group P1 with a = 10.4484(13) Å, b = 12.2015(15) Å, c = 14.0170(17) Å; α = 92.800(2)°, β = 102.7220(10)°, γ = 108.880(2)°. Z = 2, d c = 1.617 mg m?3, F(000) = 786. R1 = 0.0327, and wR2 = 0.0911.  相似文献   

15.
T The title coordination polymer including two crystallographically independent Co<'2+> ions is hydrothermally synthesized, in which the Co(1)<'2+> ion is four-coordinated by two carboxylate oxygen atoms from two different 5-(benzoic acid-4-yldiazenyl)isophthalate(byip<'3->)anions and two nitrogen atoms from two distinct 1,4-bis(imidazol-1-ylmethyl)benzene(bix)ligands displaying a tetrahedral geometry. The Co(2)<'2+> ion is six-coordinated by two water molecules at the apical positions, and two carboxylate oxygen atoms and two nitrogen atoms at the equatorial positions, affording a slightly distorted octahedron. Two Co(1)<'2+> and two Co(2)<'2+> ions are linked together by four byip<'3-> anions forming a 44-membered motif and these motifs are further arranged into a three-dimensional framework through bix ligands along the a axis with a larger channel(ca.22.70(A)×11.01(A)). Each individual network interpenetrates with the other identical network in a parallel fashion to generate a 2-fold interpenetrating array with the {6<'2>.8<'4>} {6<'3>}<,2> {6<'4>.8<'2>}<,2> topology.  相似文献   

16.
A novel compound [Cu2(EDTA)(Py)2(H2O)2]·2H2O was synthesized by the reaction of CuSO4(5H2O with H4EDTA in pyridine/water (V/V = 1/4) solvent, and characterized by elemental analysis, IR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n with a = 1.26974(6), b = 0.67949(3), c = 1.48548(3) nm, β = 91.454(2)o, V = 1.28122(9) nm3, Z = 2, Dc = 1.673 g/cm3, Mr = 645.56, F(000) = 664, μ(MoKα) = 1.729 mm-1, the final R = 0.0353 and wR = 0.0832 for 1920 observed reflections (I > 2((I)). The compound is a centrosymmetric binuclear molecule with bridged EDTA group. Each Cu(II) atom is linked to two oxygen atoms and one nitrogen atom of EDTA, one oxygen atom of water and one nitrogen atom of pyridine to form a distorted square pyramidal environment. There exist face-to-face π-π stacking interactions between pyridine rings from neighboring molecule with the interplanar distance of 0.3670 nm and hydrogen bonding between EDTA and water molecules.  相似文献   

17.
A novel complex [Ce(NO3)5(H2O)2]·2(Hphen)·(H2O) (phen =1,10-phenanthroline) with formula C24H24CeN9O18 and Mr = 866.64 has been synthesized and structurally characterized by X-ray diffraction. It crystallizes in triclinic, space group Pī with a = 7.5534(2), b = 8.083(2), c = 25.8377(6) A, α = 86.847(1), β = 89.937(1), γ = 86.981(1)o, V = 1572.94(6) A3, Dc = 1.830 g/cm3, F(000) = 866, β = 1.545 cm-1 and Z = 2. The final refinement gave R = 0.0486 and wR = 0.1278 for 4852 observed reflections with I > 2σ(I). It consists of discrete [Ce(NO3)5(H2O)2]2- anion, two Hphen+ cations and a lattice water molecule. In the compound, all of the five nitrates are bidentate, and the coordination of Ce(III) is 12. The photo-luminescence of this compound was also investigated.  相似文献   

18.
A novel coordination polymer, [Mn(PDC)H2O]n (1) (H2PDC=pyridine-2,3-dicarboxylic acid), has been hydrothermally synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. X-ray single crystal structural analyses revealed that two-dimensional frameworks were formed, and further assembled into a three-dimensional supramolecular structure bridged by PDC ligands. Moreover, the magnetic study of complex 1 shows weak antiferromagnetic interaction between the neighboring Mn(II) centers within the chains and even weak ferromagnetic interactions between the Mn(II) centers in different chains.  相似文献   

19.
A novel coordination polymer [Eu2(C6H8O4)3(H2O)2]n·n(4,4’-bpy) (Mr = 928.51) was synthesized by the hydrothermal reaction of EuCl3·6H2O, adipic acid and 4,4’-bpy, and determined by elemental analysis, IR spectroscopy, thermal gravimetric analysis, single-crystal diffraction and fluorescence property. X-ray analysis reveals that a three-dimensional network has been formed between Eu3+ by carboxyl of adipic acid. The crystal is of orthorhombic, space group Pbcn with a = 21.870(7), b = 7.652(2), c = 19.624(6) (A), V = 3284.1(17)(A)3, Z = 4, Dc = 1.878 g/cm3, μ = 3.854 mm-1, F(000) = 1824, R = 0.0345 and wR = 0.0565. The coordination polymer exhibits intensive red light under UV excitation at room temperature, which is attributed to the 5D0→7F2 transition of Eu(Ⅲ) ions.  相似文献   

20.
A new infinite three-dimensional framework structure of the title compound [H6Mo^VI8O27]·3C4N2H10 has been synthesized under mild hydrothermal conditions and characterized by elemental analyses, IR, fluorescent spectra and single-crystal X-ray diffraction. C12H36Mo8N6O27 crystallizes in the triclinic system, space group P1^- with a = 8.820(3), b = 9.534(3), c = 10.993(4)A, α= 99.985(17), β = 106.65(2), γ= 101.650(14)°,V = 840.6(5)A^3, Mr = 1463.99, Z = 1, Dc = 2.892 g/cm^3,μ = 2.993 mm^-1, F(000) = 702, the final R = 0.0676, wR = 0.1920 and S = 1.074 for 2196 observed reflections with I 〉 2σ(I). The title compound exhibits a novel infinite three-dimensional (3D) framework composed of a [H6Mo^VI8O27] subunit and three dissociated piperazine fragments. The complex exhibits two strong fluorescent emission bands at ca. 417 and 440 nm (λex = 378nm) in the solid state at room temperature.  相似文献   

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