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1.
V(2)O(5) x nH(2)O xerogel films with n = 1.6, 0.6, and 0.3 have been prepared from the sol-gel route by reacting V(2)O(5) with H(2)O(2) followed by drying under ambient conditions and thermal annealing at 110 and 250 degrees C, respectively. After dehydration, V(2)O(5) crystallizes at 300-330 degrees C, as revealed by thermal gravimetric analysis and X-ray diffraction. Electrochemical characterization demonstrated that V(2)O(5) x 0.3H(2)O film exhibits the best Li(+) intercalation performance, with an initial capacity of 275 mAh/g and a stabilized capacity of 185 mAh/g under a high current density of 100 microA/cm(2) after 50 cycles. Under a low current density of 10 microA/cm(2), the capacity of this film can reach 390 mAh/g. Such an enhanced electrochemical property by thermal treatment is ascribed to the reduced water content, the retained interlayer spacing, and the dominant amorphous phase in the film.  相似文献   

2.
Yang T  Sun J  Eriksson L  Li G  Zou X  Liao F  Lin J 《Inorganic chemistry》2008,47(8):3228-3233
Two novel isotypic polyborate cluster compounds Na 5[MB 24O 34(OH) 12]. nH 2O (M = Cr (3+), Al (3+)) have been synthesized in a boric acid flux closed system at 220 degrees C by using gel as precursors. The structure of the Cr compound was determined by low-temperature single-crystal X-ray diffraction, and the Al compound was confirmed to be isostructural by powder X-ray diffraction and similar FT-IR spectra and thermal behavior. Na 5[CrB 24O 34(OH) 12]. nH 2O crystallizes in the monoclinic space group P2 1/ c with the cell parameters a = 17.4549(3) A, b = 11.1976(2) A, c = 21.2403(3) A, beta = 94.644(2) degrees , V = 4137.85(12) A (3), and Z = 4. The predominant feature of the structure are the spherelike polyborate clusters [MB 24O 34(OH) 12] (5-). The M (3+) cation is located at the center of the cluster, around which four hexaborate units ([B 6O 10(OH) 3] (5-)) are tetrahedrally assembled in almost a perfect T d symmetry. To the best of our knowledge, [MB 24O 34(OH) 12] (5-) is the first example of a polyborate cluster that contains 24 boron atoms. Upon heating, the compounds show two steps of weight loss, including the loss of the disengaged water and dehydration of the hydroxy groups. The first step is reversible, retaining the structure framework. The second weight loss is continuous and irreversible.  相似文献   

3.
A novel one-dimensional chain-like coordination polymer constructed from 3-nitrobenzene-1,2-dicarboxylic acid, [Cd2(C8H3NO6)2(H2O)4]n·2nH2O, has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to monoclinic, space group P21/c with a = 6.1252(8), b = 20.706(3), c = 8.8067(11) (A), β = 95.608(2)°, V= 1111.6(2)(A)3, Mr =751.12, Dc = 2.244 g/cm3, F(000) = 736, μ = 2.011 mm-1, Z = 2, the final R = 0.0262 and wR = 0.0692for 2338 observed reflections with I > 2σ(I). The structure of the title compound presents a 1-D chain-like structure constructed by dimer units, [Cd2(CsH3NO6)2(H2O)4]n, through two carboxylate oxygen atoms. The fluorescence of the tifle compound has been also discussed in this paper.  相似文献   

4.
We have prepared Ni-V(2)O(5).nH(2)O core-shell nanocable arrays for Li(+) intercalation applications. Ni-V(2)O(5).nH(2)O nanocables were prepared via formation of Ni nanorod arrays through the template based electrochemical deposition, followed by coating of V(2)O(5).nH(2)O on Ni nanorods through electrophoretic deposition. Transmission electron microscopy (TEM) micrograph clearly shows the Ni core was covered completely by a V(2)O(5).nH(2)O shell. Electrochemical analysis demonstrates that in a current density of 1.6 A/g, the Li(+) intercalation capacity of Ni-V(2)O(5).nH(2)O nanocable array is approximately 10 times higher than that of single-crystal V(2)O(5) nanorod array and 20 times higher than that of sol-gel-derived V(2)O(5) film. Both energy density and power density of such nanocable-array electrodes are higher than the V(2)O(5) film electrode by at least 1 order of magnitude. Such significant improvement in electrochemical performance is due to the large surface area and short diffusion path offered by the nanostructured V(2)O(5).nH(2)O.  相似文献   

5.
A novel 5-aminoisophthalate compound, [Mn(C8H5NO4)(H2O]n(2nH2O 1, has been synthesized by the hydrothermal assembly of 5-aminoisophthalic acid with manganese acetate. Ele- mental analysis, X-ray crystal structure analyses, IR spectra, FT-Raman and ESR were carried out for the structural determination and characterization of the title compound. Compound 1 crystallizes in triclinic, space group Pī with a = 7.7562(2), b = 8.6121(3), c = 8.7107(2)(A), α = 85.411(2), β = 76.030(2), γ = 66.510(2)o, V = 517.76(3)(A)3, MnC8H11NO7, Mr = 288.12, Z = 2, Dc = 1.848 g/cm3, μ = 1.300 mm-1, F(000) = 294, R = 0.0381 and wR = 0.1043 for 1652 observed reflections (I > 2σ(I)).  相似文献   

6.
1 INTRODUCTION The self-assembly of organic-inorganic hybrid ma- terials is an intriguing area, which is yielding new generations of supramolecular architectures[1, 2]. Coor- dination by transition metals with multifunctional ligands is one of the main design principles. As a rigid multi-dentate ligand, 5-aminoisophthalic acid (AIP) has received considerable attention owing to the variety of bridging abilities[3~8]. It can engage in three types of intermolecular interactions: (1) M-L b…  相似文献   

7.
The title compound, [Mn(2,4,6-TMBA)2(H2O)3]n·2nH2O(1), where 2,4,6-TMBA=2,4,6-trimethylbenzoic acid, was synthesized and its crystal structure was determined by X-ray diffraction analysis. The crystal is of monoclinic, space group C2/c with a=2.929 9(6) nm, b=1.036 4(2) nm, c=8.222 04(17) nm, V=2.494 7(9) nm3, Z=4, M=471.40, Dc=1.255 g·cm-3, μ=0.571 mm-1, F(000)=996, Rint=0.029 4, R=0.037 6 and wR=0.094 9. The Mn atoms are octahedrally coordinated by two O atoms of two ligands and four O atoms of water. The carboxyl group coordinates to Mn(Ⅱ) in the mode of monodentate, while the O atoms of water molecules coordinates in bridging mode. The complex shows a one-dimensional chain structure bridged by water molecules. CCDC: 297750.  相似文献   

8.
1INTRODUCTIONThehydrothermalsynthesisofmetalsaltsofaro-maticpolycarboxylicacidisattractinginterestinthefieldofcrystalengineeringasaconsequenceoftheirnovelstructuresandpropertiessuchasporosityandmagneticinteractionsbetweenparamagneticmetal-ions[1~7].1,3,5-Benzenetricarboxylicacid(H3-BTC)hasreceivedconsiderableattentionasatridentatearomaticpolycarboxylicligandcapableofformingcoordinationpolymers.Manyscientistshavesuc-ceededinsynthesizingvarietyofporouscoordina-tionpolymerswithhighdimension…  相似文献   

9.
1INTRODUCTION Recently,the design and preparation of coordina-tion polymers with new porous frameworks are of great interest due to their potential functionalities such as catalysis,gas absorption,separation and molecu-lar recognition.In designing1-D,2-D and3-D porous coordination polymers,the selection of appropriate ligands is crucial for determining the structure.The mixed-linker systems of both carboxylates and pyri-dyls have proved to be effective for the preparation of novel coordi…  相似文献   

10.
A novel one-dimensional chain-like coordination polymer constructed from 3-nitro- benzene-1,2-dicarboxylic acid, [Cd2(C8H3NO6)2(H2O)4]n·2nH2O, has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to monoclinic, space group P21/c with a = 6.1252(8), b = 20.706(3), c = 8.8067(11) , β = 95.608(2)°, V = 1111.6(2) 3, Mr = 751.12, Dc = 2.244 g/cm3, F(000) = 736, μ = 2.011 mm-1, Z = 2, the final R = 0.0262 and wR = 0.0692 for 2338 observed reflections with I > 2σ(I). The structure of the title compound presents a 1-D chain-like structure constructed by dimer units, [Cd2(C8H3NO6)2(H2O)4]n, through two carboxylate oxygen atoms. The fluorescence of the title compound has been also discussed in this paper.  相似文献   

11.
1 INTRODUCTION Metal-organic coordination polymers are currently of considerable interest and importance because they can be used as new functional materials applicable in adsorption, luminescent and NLO materials fields[1, 2]. Due to the manifold N- and O-donors of pyridine- (bi)carboxylic ligands, metal pyridine-(bi)carboxyla- tes can construct versatile structural motifs, which finally aggregate to generate various supramolecular architectures with interesting properties[3, 4]. The d…  相似文献   

12.
Dai Z  Chen X  Shi Z  Zhang D  Li G  Feng S 《Inorganic chemistry》2003,42(3):908-912
Two inorganic-organic hybrid compounds with the formula M(4,4'-bipy)(H(2)O)V(2)Se(2)O(10) (M = Co, Ni) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compounds Co(4,4'-bipy)(H(2)O)V(2)Se(2)O(10) (1) and Ni(4,4'-bipy)(H(2)O)V(2)Se(2)O(10) (2), which are structural analogues, crystallize in the triclinic space group Ponemacr; with crystal data a = 7.9665(3) A, b = 8.1974(3) A, c = 13.8096(4) A, alpha = 85.704(2) degrees, beta = 73.5180(10) degrees, gamma = 75.645(2) degrees, V = 837.76(5) A(3), and Z = 2 and a = 7.9489(19) A, b = 8.128(2) A, c = 13.709 A, alpha = 85.838(6) degrees, beta = 73.736(8) degrees, gamma = 75.594(9) degrees, V = 823.5(4) A(3), and Z = 2, respectively. [M(4,4'-bipy)(H(2)O)V(2)Se(2)O(10)] (M = Co, Ni) have a three-dimensional structure and consist of two subunits, [(VO(2))(SeO(3))](-) infinite chains and [M(4,4'-bipy)(H(2)O)](2+) fragments. The [(VO(2))(SeO(3))](-) chains are composed of [V(2)Se(4)O(14)](4)(-) clusters linked by VO(4)N triangular bipyramids. The 4,4'-bipy molecule as a bifunctional organic ligand is directly linked to Co or Ni and V atoms, affording the three-dimensionality. The compounds were characterized by infrared spectroscopy and differential thermal and thermogravimetric analyses.  相似文献   

13.
Naruke H  Yamase T 《Inorganic chemistry》2002,41(24):6514-6520
Single crystals of R(2)Mo(5)O(18) and R(6)Mo(12)O(45) (R = Eu and Gd), which are novel compounds in the R(2)O(3)-MoO(3) system, have been obtained by thermal decomposition of [R(2)(H(2)O)(12)Mo(8)O(27)].nH(2)O in air at 750 degrees C for 2 h. TG-DTA and X-ray diffractometry showed that R(2)Mo(5)O(18) crystallizes in a melt of the dehydrated precursor (R(2)Mo(8)O(27)), and R(2)Mo(5)O(18) is transformed to R(6)Mo(12)O(45) in the solid state, both occurring with the loss of MoO(3). R(2)Mo(5)O(18) species crystallize isostructurallyas orthorhombic, Pbcn, Z = 4, with lattice constants of a = 19.2612(7) and 19.246(1) A, b = 9.4618(3) and 9.4414(5) A, c = 9.3779(3) and 9.3446(4) A for R = Eu and Gd, respectively. R(6)Mo(12)O(45) crystallize isostructurally as triclinic P1, Z = 1, with lattice constants of a = 9.3867(4) and 9.3409(3) A, b = 10.9408(5) and 10.8826(5) A, c = 11.4817(5) and 11.4377(5) A, alpha = 104.194(2) degrees and 104.170(1) degrees, beta = 109.567(3) degrees and 109.288(4) degrees, gamma = 108.998(2) degrees and 109.266(2) degrees for R = Eu and Gd, respectively. Both structures consist of [RO(8)] square-antiprisms and [MoO(n)] polyhedra. In R(2)Mo(5)O(18), an [RO(8)] polyhedron is attached by only molybdate groups, being isolated from adjacent [RO(8)] groups. The 12 nearest R atoms surrounding an R atom with R...R distances of 6.0735(4)-7.0389(4) A form an approximate cuboctahedron. All the [RO(8)] square-antiprisms in R(6)Mo(12)O(45) are connected to each other by face-sharing to form dimeric [R(2)O(13)] and [R(2)O(12)] groups. The latter unusual [R(2)O(12)] group is achieved by sharing a square-face via four bridging O atoms with a very short R...R separation (3.4741(7) and 3.4502(6) A for R = Eu and Gd, respectively).  相似文献   

14.
Two new vanadates, Ba(2.5)(VO2)3(SeO3)4.H2O and La(VO2)3(TeO6).3H2O, have been synthesized by hydrothermal methods using BaCO3, Ba(OH)2.H2O, La(NO3)3.6H2O, V2O5, TeO2, and H2SeO3 as reagents. The structures were determined by single-crystal X-ray diffraction. Ba(2.5)(VO2)3(SeO3)4.H2O exhibits a two-dimensional layered structure consisting of VO(5) square pyramids and SeO3 polyhedra, whereas La(VO2)3(TeO6).3H2O has a three-dimensional framework structure composed of VO(4) tetrahedra and TeO6 octahedra. Infrared and Raman spectroscopy, UV-vis diffuse reflectance spectroscopy, and thermogravimetric analysis are also presented. Crystal data: Ba(2.5)(VO2)3(SeO3)4.H2O, trigonal, space group P (No. 147) with a = b = 12.8279(15) A, c = 7.2631(9) A, V = 1035.1(2) A(3), and Z = 2; La(VO2)3(TeO6).3H2O, trigonal, space group R3c (No. 161) with a = b = 9.4577(16) A, c = 23.455(7) A, V = 1816.9(7) A3, and Z = 6.  相似文献   

15.
<正> The crystal and molecular structure of the title compound was determined by means of Patterson and Fourier synthesis based on three-dimensional X-ray data. The crystallographic parameters are as follows; (C13H8NOCl)2Co, monoclinic, space group A2/a,a = 11. 722 (8) , b = 8. 726 (5) , c = 21. 810 (8) A ,β= 95. 90 (6)°, V = 2219. OA3,Z= 4, Dc=1.55g/cm3,μ= 10. 71cm-1, F(000) = 1052, R= 0.042, Rw = 0. 051. Two iminato ligands are attached to the center atom Co through their donor atoms N(1),O(1),N(1)* ,and O(1)* to form a distorted tetrahedral configuration. The bond lengths of Co-O and Co-N are 1. 891 and 1. 988 A , respectively.  相似文献   

16.
Hydrothermal reactions of the V2O5/2,2':6':2"-terpyridine/ZnO/H2O system under a variety of conditions yielded the organic-inorganic hybrid materials [V2O4(terpy)2]3[V10O28].2H2O (VOXI-10), [VO2(terpy)][V4O10] (VOXI-11), and [V9O22(terpy)3] (VOXI-12). The structure of VOXI-10 consists of discrete binuclear cations [V2O4(terpy)2]2+ and one-dimensional chains [V10O28]6-, constructed of cyclic [V4O12]4- clusters linked through (VO4) tetrahedra. In contrast, the structure of VOXI-11 exhibits discrete mononuclear cations [VO2(terpy)]1+ and a two-dimensional vanadium oxide network, [V4O10]1-. The structure of the oxide layer is constructed from ribbons of edge-sharing square pyramids; adjacent ribbons are connected through corner-sharing interactions into the two-dimensional architecture. VOXI-12 is also a network structure; however, in this case the terpy ligand is incorporated into the two-dimensional oxide network whose unique structure is constructed from cyclic [V6O18]6- clusters and linear (V3O5(terpy)3) moieties of corner-sharing vanadium octahedra. The rings form chains through corner-sharing linkages; adjacent chains are connected through the trinuclear units. Crystal data: VOXI-10, C90H70N18O42V16, triclinic P1, a = 12.2071(7) A, b = 13.8855(8) A, 16.9832(10) A, alpha = 69.584(1) degrees, beta = 71.204(1) degrees, gamma = 84.640(1) degrees, Z = 1; VOXI-11, C15H11N3O12V5, monoclinic, P2(1)/n, a = 7.7771(1) A, b = 10.3595(2) A, c = 25.715(4) A, beta = 92.286(1) degrees, Z = 4; VOXI-12, C45H33N9O22V9, monoclinic C2/c, a = 23.774(2) A, b = 9.4309(6) A, c = 25.380(2) A, beta = 112.047(1) degrees, Z = 4.  相似文献   

17.
A metal-organic coordination polymer [Co(phen)(BDC)(H2O)]n·0.5nH2BDC(H2BDC = terephthalic acid, phen = 1,10-phenanthroline) has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in triclinic, space group P1- with a = 9.771(3), b =10.739(3), c= 11.249(4) (A), α = 75.946(3), β = 65.306(3), γ = 86.073(4)°, V = 1039.6(6)(A)3, C24H17CoN2O7, Mr=504.33, Dc = 1.611 g/cm3, μ(MoKa) = 0.878 mm-1, F(000) = 516, Z = 2, the final R = 0.0547 and wR = 0.1138 for 2916 observed reflections (I> 2σ(Ⅰ)). It exhibits a one-dimensional zigzag chain-like structure.  相似文献   

18.
Dai Z  Shi Z  Li G  Zhang D  Fu W  Jin H  Xu W  Feng S 《Inorganic chemistry》2003,42(23):7396-7402
A family of inorganic-organic hybrid vanadium selenites with zero-, one-, two-, and three-dimensional structures, (1,10-phen)(2)V(2)SeO(7), (2,2'-bipy)VSeO(4), (4,4'-bipy)V(2)Se(2)O(8), and (4,4'-bipy)(2)V(4)Se(3)O(15).H(2)O (where phen = phenanthroline and bipy = bipyridine), were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Different bidentate organodiamine ligands and reactant concentrations were used in the four reaction systems, which are responsible for the variety of structural dimensions of the compounds. (1,10-phen)(2)V(2)SeO(7) crystallizes in a monoclinic system with space group P2(1)/n and cell parameters a = 8.6509(3) A,( )b = 7.8379(2) A, c = 34.0998(13) A, beta = 91.503(2) degrees, and Z = 4. (2,2'-bipy)VSeO(4) crystallizes in a monoclinic system with space group C2/c and cell parameters a = 17.0895(12) A, b = 14.7707(10) A, c = 11.7657(8) A, beta = 131.354(3) degrees, and Z = 8. (4,4'-bipy)V(2)Se(2)O(8) crystallizes in a triclinic system with space group Ponemacr; and cell parameters a = 7.1810(10) A, b = 10.8937(13) A, c = 11.1811(15) A, alpha = 115.455(3) degrees, beta = 107.582(3) degrees, gamma = 91.957(4) degrees, and Z = 2. (4,4'-bipy)(2)V(4)Se(3)O(15).H(2)O crystallizes in a monoclinic system with space group Pc and cell parameters a = 7.9889(9) A, b = 7.8448 A, c = 23.048(3) A, beta = 99.389(4) degrees, and Z = 2. (1,10-phen)(2)V(2)SeO(7) has an isolated structure, (2,2'-bipy)VSeO(4) has a chain structure, (4,4'-bipy)V(2)Se(2)O(8) has a layered structure, and (4,4'-bipy)(2)V(4)Se(3)O(15).H(2)O has a framework structure. The chains are constructed from VO(4)N(2) octahedra and SeO(3) pyramids, laced by organic ligands (2,2'-bipy). The layers consist of vanadium selenite chains [(VO)(2)(SeO(3))(2)]( infinity ), linked by 4,4'-bipy molecules. The framework is composed of vanadium selenite sheets [V(4)Se(3)O(16)]( infinity ), pillared by 4,4'-bipy molecules. All of the compounds are thermally stable to 300 degrees C, and the magnetic susceptibilities confirm the existence of tetravalent V atoms in the antiferromagnetic (4,4'-bipy)V(2)Se(2)O(8) complex and mixed tetravalent and pentavalent V atoms in the paramagnetic complex (4,4'-bipy)(2)V(4)Se(3)O(15).H(2)O.  相似文献   

19.
在水-吡啶混合体系中, 以5-羟基-1,3-苯二甲酸(简作HO-H2BDC )、1,2-二(4-吡啶)乙烷(简作bpe)为配体与Co(NO3)2·6H2O反应, 培养出[Co2(HO-BDC)2(bpe)2(H2O)2]n·n(py)·nH2O(py=pyridine)的紫色单晶, 该晶体属三斜晶系, P1空间群, 晶胞参数a=1.0245(3) nm, b=1.1467(3) nm, c=1.2430(4) nm, α=68.915(5)°, β=67.163(4)°, γ=71.373(4)°, V=1.2279(6) nm3, Z=1, Mr=979.70, Dc=1.325 Mg/m3, F(000)=506, μ=0.740 mm-1, R1=0.0515, wR2=0.1058. 该配位聚合物中在ac平面上具有规则平行四边形纳米尺寸的孔, 其孔径大小约为1.025 nm×1.354 nm, 而且通过氢键相互作用连成具有双层结构的2D网络结构. TGA曲线表明, 配位聚合物的失重发生在110~150 ℃之间, 总失重约为80.1%, 最终产物为Co2O3.  相似文献   

20.
Three new strontium vanadium borophosphate compounds, (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O (Sr-VBPO1) (1), (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O (Sr-VBPO2) (2), and (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4][V2P2BO12]6 10H2O (Sr-VBPO3) (3) have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane. Compound 1 has a chain structure, whereas 2 and 3 have layered structures with different arrangements of [(NH4) [symbol: see text] [V2P2BO12]6] cluster anions within the layers. Crystal data: (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 21.552(1) A, b = 27.694(2) A, c = 20.552(1) A, beta = 113.650(1) degrees, Z = 4; (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O, monoclinic, space group I2/m (no. 12), a = 15.7618(9) A, b = 16.4821(9) A, c = 21.112(1) A, beta = 107.473(1) degrees, Z = 2; (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4] [V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 39.364(2) A, b = 14.0924(7) A, c = 25.342(1) A, beta = 121.259(1) degrees, Z = 4. The differences in the three structures arise from the different steric requirements of the amines that lead to different amine-cluster hydrogen bonds.  相似文献   

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