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21.
WEI Yi-Jun  WANG Feng-Wu  ZHU Qi-Yong   《结构化学》2007,26(11):1337-1340
The title mononuclear Schiff base nickel(Ⅱ) complex [Ni(C11H14Br2N2O)2(H2O)2]·2NO3·2C2H3N was prepared and characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 15.534(2), b = 7.647(1), c = 16.435(2) (A), β = 103.252(2)o, V = 1900.3(4) (A)3, Z = 2, Dc = 1.750 g/cm3, Mr = 1000.99, λ(MoKα) = 0.71073 (A), μ = 4.776 mm-1, F(000) = 996, the final R = 0.0368 and wR = 0.0724. A total of 3988 unique reflections were collected, of which 2764 with I>2σ(I) were observed. The complex consists of a mononuclear [Ni(C11H14Br2N2O)2(H2O)2]2 cation, two nitrate anions and two acetonitrile molecules. The Ni atom, lying on the inversion centre, is six- coordinated by two Schiff bases and two water molecules to assume an octahedral coordination geometry. The molecules in the crystal are linked through intermolecular hydrogen bonds of N-H…O, N-H…Br, O-H…O, O-H…N and C-H…O to form layers.  相似文献   
22.
Mg and Al alkoxide complex was synthesized in a cell without battery separator by electrochemical dissolution of aluminum for 6 h and magnesium for 1.8 h at 45 ℃ in ethanol solution of 0.04 mol·dm-3 (Bu4N)Br with a current density of 100 mA·cm-2. IR and Raman spectroscopy were used to characterize the structure of the precursor of MgAl2O4. The results show that the current efficiency attains 98.4% and the precursor is MgAl2(OCH2CH3)5(acac)3. The acac- group-containing precursor could prevent it from agglomeration. The xerogel was obtained by drying in vacuum for 24 h and hydrolysis under pH≈8.5 of the precursor, which was heated at 350 ℃ for 2 h to obtain the nano-MgAl2O4 powder. XRD and TEM were used to investigate the structure of nano-MgAl2O4. The result suggests that the xerogel with an average particle size of 10 nm and the Nano-sized Spinel MgAl2O4 Particle of 12 nm thus obtained are with high purity.  相似文献   
23.
The solution reactions of the metal salts with 2,2'-bipyfidine (2,2'-bipy) and ethyl tetrazole-5-carboxylate (Hetzc) afforded two new tetrazole-based complexes M(2,2'-bipy)2(etzc)2 (M=Mn 1, Zn 2), and their crystal structures were determined by single-crystal X-ray diffraction analyses. Crystallographic data for 1: C28H26MnN12O4, Mr = 649.55, monoclinic, space group C2/c, a= 19.326(15), b = 11.051(6), c = 16.388(13)А,β= 117.38(4)° V= 3108(4) А^3, Z= 4, Dc = 1.388 g/cm^3, F(000) = 1340, R = 0.0557 and wR = 0.1269; and those for 2: C28H26ZnN12O4, Mr = 659.98, monoclinic, space group C2/c, a = 19.173(4), b = 11.006(2), c = 16.266(4) А, β= 118.11(3)°, V= 3027.4(11) А^3, Z = 4, Dc=1.448 g/cm3, F(000) = 1360, R = 0.0428 and wR = 0.1000. The structures of 1 and 2 are isomorphic and consist of isolated neutral mononuclear units. The metal atoms have highly distorted octahedral coordination environments with two N atoms from two etzc ligands and four N atoms from two 2,2'-bipy molecules. The isolated mononuclear units are connected by π…π stacking interactions to generate one-dimensional chains. The thermal stability and photoluminescence have also been discussed.  相似文献   
24.
A series of non-isocyanate linear high molecular weight poly(ester urethane)s(PETUs)were prepared through an environmentallyfriendly route based on dimethyl carbonate,1,6-hexanediol and 1,6-hexanediamine.In this route,the polyurethane diol was first prepared by the reaction between bis-1,6-hexamethylencarbamate(BHC)and 1,6-hexanediol.A series of polyester soft segments of polyurethane have been synthesized from the polycondensation of adipic acid and different diols,including butanediol,hexanediol,octanediol and decanediol.The subsequent polycondensation of polyurethane diol and polyester diol led to linear PETUs.The resultant polymers were characterized by GPC,FTIR,1H-NMR,13C-NMR,DSC,WAXD,TGA and tensile test.The results indicated that PETUs possess weight-average molecular weights higher than 1×105 and the tensile strength as high as 10 MPa.The thermal properties,crystallization behavior,microphase separation behavior and morphology were studied by DSC and AFM,and the results indicated that the degree of phase separation was affected by two factors,the crystallization and hydrogen bonding interaction between soft segment and hard segment.  相似文献   
25.
The title mononuclear Schiff base nickel(Ⅱ) complex [Ni(C11H14Br2N2O)2(H2O)2]·2NO3·2C2H3N was prepared and characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 15.534(2), b = 7.647(1), c = 16.435(2) (A), β = 103.252(2)o, V = 1900.3(4) (A)3, Z = 2, Dc = 1.750 g/cm3, Mr = 1000.99, λ(MoKα) = 0.71073 (A), μ = 4.776 mm-1, F(000) = 996, the final R = 0.0368 and wR = 0.0724. A total of 3988 unique reflections were collected, of which 2764 with I>2σ(I) were observed. The complex consists of a mononuclear [Ni(C11H14Br2N2O)2(H2O)2]2 cation, two nitrate anions and two acetonitrile molecules. The Ni atom, lying on the inversion centre, is six- coordinated by two Schiff bases and two water molecules to assume an octahedral coordination geometry. The molecules in the crystal are linked through intermolecular hydrogen bonds of N-H…O, N-H…Br, O-H…O, O-H…N and C-H…O to form layers.  相似文献   
26.
Zou WQ  Wang MS  Li Y  Wu AQ  Zheng FK  Chen QY  Guo GC  Huang JS 《Inorganic chemistry》2007,46(17):6852-6854
A metal-organic framework with the highest connectivity of 2-D topology was first assembled from an octacobalt(II) cluster as a 10-connected node and a new bifunctional ligand 1-(3,5-dicarboxy-phenyl)-4-phenyl-1H-1,2,3-triazole as a 3-connected node as well as "double bridge" linkers.  相似文献   
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