Hydrothermal Synthesis, Crystal Structure and Photoluminescent Property of a Zinc(II) Coordination Polymer Assembled by Phthalate and 4,4''-Bipyridine

A metal-organic coordination polymer {[Zn(Pht)(4,4′-bipy)(H2O)2]·2H2O}n (Pht = phthalate, 4,4′-bipy = 4,4′-bipyridine) 1 has been hydrothermally synthesized and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. Yellow crystals crystallize in the monoclinic system, space group P2/n, a = 7.6346(14), b = 11.316(2), c = 10.8133(19) (A), β = 92.444(3)o, V = 933.3(3)(A)3, C18H20N2O8Zn, Mr = 457.73, Dc = 1.629 g/cm3, F(000) = 472, Z = 2, μ(MoKα) = 1.367 mm-1, the final R = 0.0323 and wR = 0.0821 for 1859 observed reflections (I > 2σ(I)). The structure of 1 exhibits a two-dimensional bilayer framework formed by hydrogen bonding interactions. Furthermore, 1 shows yellow photoluminescent pro- perty at room temperature.     

Hydrothermal Synthesis, Crystal Structure and Photoluminescent Property of a New Isophthalatebridged Zinc(Ⅱ) Polymer with One-dimensional Chain Structure: [Zn(ipt)(im)2]2n·3nH2O(ipt = Isophthalate, im = Imidazole)

A new metal-organic coordination polymer [Zn(ipt)(im)2]2n(3nH2O 1 has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/n with a = 10.653(3), b = 17.891(6), c = 10.743(4)(A), β = 117.093(5)°, V = 1822.9(10)(A)3, Mr = 413.65, Dc = 1.507 g/cm3, μ(MoKα) = 1.390 mm-1, F(000) = 840, Z = 4, the final R = 0.0444 and wR = 0.1066 for 2434 observed reflections (I > 2σ(I)). Furthermore, compound 1 shows blue photoluminescent property at room temperature.     

Pellet Enhanced Performance on the HL-2A Tokamak

Enhanced confinement has been achieved by the centre fuelling of pellet injection on the HL-2A tokamak. The energy confinement time increases from 50ms to 140ms after the pellet injection. Experimental results show that the improvement of the confinement is related to the decrease of the electron heat transport. Several phenomena which may lead to the improved confinement have been observed in the experiments. After the pellet injection the hollow electron temperature profile and the peaked electron density profile can be sustained for about 200ms, but the improved confinement remains at about 500ms. Sawtooth features and MHD modes have been observed by soft x-ray array and the Mirnov probes. The weak （or reversed） magnetic shear is thought to be an important cause of the low electron heat transport.     

Synthesis,Crystal Structure and Characterization of a Cobalt Coordination Polymer： [Co（bib）（L）]-0.5H2O

The title coordination polymer, [Co（bib）（L）].0.5H2O 1 （bib = 1,1＇-（1,4-butanediyl）bis（imidazole） and L = 4,4＇-oxy（bisbenzoate） has been hydrothermally synthesized and characterized by IR and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group Cc with a = 8.8568（5）, b = 19.936（1）, c = 26.209（2） γ, y = 97.510（1）°, V= 4587.8（5） A3, Z = 8, CoC24H23N4O5.5, Mr = 514.39, Dc = 1.489 g/cm3, F（000） = 2128, μ（MoKa） = 0.795 mm^-1, R = 0.0419 and wR = 0.1002. Compound 1 exhibits a rare two-fold interpenetrating CdSO4 type topology. The O-H...O hydrogen bonds stabilize the structure of 1.     

Synthesis,Crystal Structure and Theoretical Calculations of a New Two-dimensional Co(Ⅱ) Coordination Polymer Based on Oxalic Acid and Bis(imidazol) Ligands

A new Co(Ⅱ) coordination polymer has been successfully synthesized under hydrothermal conditions [Co(C2O4)(mbix)]n(1, H2C2O4 = oxalic acid, mbix = 1,3-bis(imidazol-1-ylmethyl)benzene). Its structure has been determined by elemental analyses, IR, UV spectroscopy and single-crystal X-ray diffraction analysis. Pink crystals crystallize in the triclinic system, space group P1 with a = 8.8666(7), b = 9.5859(8), c = 10.8537(9) , α = 67.6810(10), β = 66.1260(10), γ = 77.1300(10)°, V = 777.77(11), C16H14CoN4O4, Mr = 385.24, Dc = 1.645 g/cm3, F(000) = 394, Z = 2, μ(Mo Kα) = 1.134 mm-1, the final R = 0.0482 and w R = 0.1231 for 2968 observed reflections(Ⅰ 2σ(Ⅰ)). It shows a two-dimensional(2D) network structure. The intermolecular C–H···O hydrogen bonding and π-π stacking interactions extend complex 1 into a 3D supramolecular architecture andplay an important role in stabilizing 1. In addition, Natural Bond Orbital(NBO) analysis was performed by using the PBE0/LANL2 DZ method built in Gaussian 09 Program. The calculation results showed obvious covalent interaction between the coordinated atoms and Co(Ⅱ) ion.     

Bi2MoO6/BiVO4异质结的水热合成和可见光催化活性

采用一步水热法制备Bi₂MoO₆/BiVO₄复合光催化剂. 利用X 射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、高分辨透射电子显微镜(HRTEM)等手段对其晶体结构和微观结构进行了表征. 结果表明, Bi₂MoO₆纳米粒子沉积在BiVO₄纳米片表面从而形成异质结结构. 紫外-可见漫反射光谱(UV-Vis DRS)表明所制备的Bi₂MoO₆/BiVO₄异质结较纯相Bi₂MoO₆和BiVO₄对可见光吸收更强. 由于形成异质结结构及其光吸收性能使Bi₂MoO₆/BiVO₄ 光催化活性有较大提高. 可见光下(λ>420 nm)光催化降解罗丹明B (RhB)实验结果表明,Bi₂MoO₆/BiVO₄光催化活性较纯相Bi₂MoO₆和BiVO₄高. Bi₂MoO₆/BiVO₄样品光催化性能提高的原因是Bi₂MoO₆和BiVO₄形成异质结, 从而有效抑制光生电子-空穴对的复合, 增大了可见光吸收范围及比表面积.     

Synthesis and Crystal Structure of a Novel Tetravanadate Modified by Chiral Racemoid Zirconium Complex

1 INTRODUCTION Polyoxometalate anions are a broad class of dis- crete metal-oxide compounds MxOyn–, which are of both fundamental and practical interest in a range of areas, including catalysis, biochemistry, medicine and solid state devices[1~6]. Recently, the structural chemistry of vanadium oxides in combination with secondary metal-ligand cations has attracted much attention[7~17]. These hybrid materials manifest the structural influences both of coordination preferen- ces of the sec…     

Hydrothermal Synthesis and Crystal Structure of a Cadmium(Ⅱ) Polymer with One-dimensional Chain Structure: [Cd(bpy)(BDC)]n·nbpy

A metal-organic coordination polymer [Cd(bpy)(BDC)]n·nbpy (bpy = 2,2'-bipyri- dine, H2BDC = terephthalic acid) has been hydrothermally synthesized and structurally characteri- zed by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723(5), b = 21.695(5), c = 7.576(5)(A), β = 116.171(7)o, V = 2319.3(18)(A)3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm3, μ(MoKα) = 0.987 mm(1, F(000) = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections (Ⅰ ＞ 2σI)). It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C-H…O hydrogen bonds and significant aromatic π-π stacking interactions.     

Hydrothermal Synthesis, Crystal Structure and Magnetic Properties of a Novel Zero-dimensional Manganese(Ⅱ) Complex with 2,2''-Diphenic Acid and 1,10-Phenanthroline Ligands

A novel metal-organic coordination polymer [Mn3(2,2'-dipha)3(phen)6]n·3nH2O (2,2'-dipha = 2,2'-diphenic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and magnetic susceptibility measurements. The crystal crystallizes in triclinic, space group P1- with a = 16.921(5), b = 18.307(5), c = 18.450(5) (A), α = 113.369(5), β = 108.529(5), γ = 102.984(5)° , V = 4553(2) (A)3, C114H72Mn13N12O14.25, Mr = 2002.66, Dc = 1.461 g/cm3, λ(MoKα)= 0.488 mm-1, the final F(000) = 2058, Z = 2, R = 0.0491 and wR = 0.0980 for 9087 observed reflections (Ⅰ＞2σ(Ⅰ)). In the crystal structure, the manganese atom is six-coordinated with two carboxylate oxygen atoms from different carboxylate groups of the same dipha and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Furthermore, it exhibits a zero-dimensional structure with dipha-Mn-phen- as building units. Variable-temperature magnetic measure shows an overall anti-ferromagnetic behavior for compound 1.