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Under hydrothermal conditions, six uranium coordination polymers were obtained by employing the ligand of tris(2-carboxyethyl) isocyanurate (H3tci) and different combinations of d-block metal ions ...

Two uranyl complexes based on pyromellitic acid were hydrothermally synthesized, and their X-ray single-crystal diffraction structures were determined. Complex [UO2(Hbtec)]–(Himd)+·H2O (1) (H4btec = pyromellitic acid, imd = imidazole), is an ionic complex, which shows a typical (4, 4) topological structure in the space. A heterometallic complex, UO2Cu(btec)(phen) (2) (phen = 1,10-phenanthroline) results from the reaction of uranyl nitrate and copper(II) bromide with pyromellitic acid. The structure of complex 2 revealed that the chains of UO7 and CuO3N2 units were connected to each other through the carboxyl groups and U=O–Cu interactions to create a two-dimensional framework.

Two mononuclear five-coordinated transition metal complexes FeLCl2 (I) and MnLCl2 (II) containing tridentate 2,6-bis(6-methylquinolin-2-yl)pyridine ligand (L) have been synthesized and characterized by single-crystal X-ray crystallography. In the complexes, the metal center was tridentately chelated by ligand and further coordinated by two chlorine atoms, resulting in distorted trigonal-bipyramidal geometry for complex I and II, respectively. In addition, crystal packing in complex is stabilized by C-H⋯Cl intermolecular hydrogen bond, which link the mononuclear complex to the 1D chain.

Shear mechanism of the cross bore slab of tubular hollow slab on cast-in-place concrete is set forth. Shear force and normal stress are calculated for each section of cross bore slab of tubular hollow slab with supported in one-way direction. We can put forward suggestions based on the three conditions. One condition is that shearing stress is no more than shearing resistance on cross bore slab. Another is that tensile stress on rib of cross bore slab is no more than tensile strength of the concrete. The last one is that concrete shearing stress on rib of parallel bore slab is less than its shearing resistant strength. Meanwhile one example is given. So that we can obtain the requirements for minimum rib between bores of tubular hollow slab.

To accord with the requirements of large area soft foundation treatment project, did the construction field monitoring and detection test including surface subsidence, pore water pressure, deep horizontal displacement, cone penetration test, vane shear test, and so on, make an effective and timely assessment with the construction quality and the reinforcement effect of foundation treatment project.

A novel silver complex [Ag(dafo)2(NO3)] (dafo = 4,5-diazafluoren-9-one) was obtained. Its structure was determined by single crystal X-ray diffraction. The crystal structure shows that the Ag atom is in a five coordination environment. As far as the rigid of the dafo molecular is concerned, the structure is very remarkable. The work also studies the interaction between the complex and DNA by optical special and electrochemical methods. It is found that the action mode of the complex with DNA is intercalative. A novel silver complex [Ag(dafo)2(NO3)] (dafo = 4,5-Diazafluorene-9-one) was obtained and its structure was determined by single crystal X-ray diffraction. The binding of the complex to calf thymus DNA has been investigated. It is found that the action mode of the complex with DNA is intercalative.

In an attempt to synthesize supra-molecular complex of copper (II) with mixed ligands in a solution reaction of Cu(ClO4)2· 6H2O with 4,5-diazafluorene-9-one (dafo) and o-phthalic add, the bright blue column-like crystal [Cu(dafo)2(H2O)2]-(ClO4)2 was obtained. Its structure was determined by single-crystal X-ray diffraction study. The crystal belongs to monoclinic system, space group P2(1)/n with cell dimensions: a = 0.7547(3) nm, b = 1.2021(5) nm, c = 1.3190(5) nm, α = 90.000(5)°, β = 90.000(5)°, γ = 90.000(5)°, V = 1.2600(9) nm3, Z = 2, F(000)=670, Mr = 662.83, Dc = 1.747 g/cm3, μ (Mo Kα) = 1.154 mm−1, R1, = 0.0455, wR2 = 0.1041. The analysis of the crystal structure indicates that the complex has a two-dimensional network structure which is formed by hydrogen bonds.

A novel one-dimensional chain complex [Zn(dafo)2(H2O)2](NO3)2 was obtained when we tried synthesizing a mixed ligand supramolecular compound of Zinc(II) with dafo and o-phthalic acid. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to triclinic system, P-1 space group. The crystallographic data: a=0.6989(4) nm, b=0.8281(5) nm, c=1.0231(5) nm, α=94.934(5)°, β=91.366(7)°, γ=99.820(7)°, V=0.5809(5) nm3, Z= 1, F(000)=300, Mr=589.78, Dc=1.686 g/cm3, μ(Mo Kα)=1.130 mm−1, R1=0.0521, wR2=0.1096. The analysis of the crystal structure indicates that the compound has a one-dimensional chain structure which is formed by hydrogen bonds. The constitutes of the title complex were proved by elemental analysis, IR spectra and thermal analysis. On the basis of the experimentation, the complex was calculated by DFT-B3LW/LANL2DZ in Gaussian-98w also.

In an attempt to synthesize a new pyrimidine complex of copper(II) in a solution reaction of CuBr2 with 2,2′-bis(hexahydropyrimidine) and hydro-chloric acid, we unexpectedly obtained a bright yellow chip-like crystal of CuC4(H2tn) [H,tn=(H3NCH2CH2CH2NH3)2+]. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group Pnma, with cell parameters: a=0.7216(2) nm, b= 1.8308(6) nm, c=0.7553(3) nm, V=0.9953(6) nm3, Z=4, F(000)=564, Mr=281.49, D,= 1.879 g/cm3. μ(Mo Ka)=3.204 m−1, R1=0.0248, wR2=0.0575. The analysis of the crystal structure indicates that the complex has a three-dimensional network structure, which is formed by hydrogen bonds and electrostatic interaction.

Four new nickel(II) and cobalt(II) complexes of Schiff base ligands: [Ni(L)Cl2]·2H2O (I), [Ni(L)(H2O)2] (NO3)2 (II), [Ni(L)(H2O)2] (ClO4)2 (III), and [Co(L) (H2O)2] (NO3)2 (IV) (L = 1,3-[bis(pyridine-2-imino)]propane) have been synthesized. The four complexes have been fully characterized by elemental analysis, IR, absorption spectra, emission spectra, and single-crystal X-ray diffraction analysis. The binding of the four complexes to calf thymus DNA (CT DNA) has been investigated by absorption spectra and emission spectra. The results of the two methods indicate that the action mode of complex I with DNA is intercalative mainly, and the action mode of complexes II, III, IV with DNA cannot be concluded, it should be sustained by other experimental measurements. Four new nickel(II) and cobalt(II) complexes of Schiff base ligands: [Ni(L)Cl2]·2H2O (I), [Ni(L)(H2O)2] (NO3)2 (II), [Ni(L)(H2O)2] (ClO4)2 (III), and [Co(L) (H2O)2] (NO3)2 (IV) (L = 1,3-[bis(pyridine-2-imino)]propane) were synthesized and their crystal structures were determined. The binding of the four complexes to calf thymus DNA (CT DNA) has been investigated.

A symmetric five-dentate Schiff-base ligand N,N-bis(pyridine-2-carboxaldehyde)diethylenetriamine (L) was prepared. An unusual copper(II) complex [CuCl2 (L)] · H2O was obtained, when copper chloride reacted with ligand L. In the course of the coordination reaction, a ring closure reaction happens to ligand L. So, the formation process of the complex can be used for reference to synthesize the ring compound. The complex has been characterized fully by elemental analysis, IR, absorption spectra, emission spectra, and single-crystal X-ray diffraction analysis. Moreover, a reasonable reaction mechanism for forming the complex was presumed. The complex was synthesized by treating an ethanolic solution of the appropriate ligand with an equimolar amount of metallic salt. In the complex, the copper atom is five-coordinated, which can be best described as a distorted square-pyramidal geometry with a N3Cl2 donor set, and two parallel one-dimensional chains are formed by packing of the complex.

Five copper complexes with 4,5-diazafluoren-9-one have been reported. Some of their structures are determined by single crystal X-ray diffraction. On the basis of experimentation, all the complexes were calculated by DFT-B3LYP/LANL2DZ in Gaussian-98w. By analyzing the experimental and calculated values, it can be concluded, on the one hand, that the experimental results are proved thoroughly by the theoretical calculated results; on the other hand, the theoretical calculated results can deduce the experimental results reasonably well.

Two new multi-nuclear homometallic complexes, [Cu2(OAc)4(H2O)2]·2dafo (1) and [(µ2-O)2-Co3(dafo)6]-(ClO3)2·H2O (2) (dafo=4,5-diazafluoren-9-one), were synthesized. The two complexes have been fully characterized by elemental analysis, IR, absorption spectra, emission spectra, and single-crystal X-ray diffraction analysis. The initial DNA binding mechanisms of the two complexes have been investigated by absorption spectra, emission spectra and cyclic voltammograms. Both complexes show similar perturbations on addition of calf thymus DNA in the UV region, their luminescence intensities in aqueous buffer are all enhanced in the presence of increasing amounts of DNA, and their electrochemical behavior is both completely different in the absence and presence of DNA. The results of the three methods indicate that the spectral characters and the electrochemical behavior of the two complexes are very similar to those of the known metallointercalators. So it can be concluded that the action mode of the two complexes with DNA is mainly intercalative.

Two new complexes [Cu(dafo)2(en)](ClO4)2·2H2O (en=NH2CH2CH2NH2) 1 and [Cu(dafo)2(dap)](ClO4)2· 2H2O [dap=NH2CH2CH(CH3)NH2] 2 (dafo=4,5-diazafluoren-9-one) have been synthesized and characterized by elemental analysis, IR and UV spectra. Meanwhile, the complex 1 has been characterized by single crystal X-ray diffraction analysis. The initial DNA binding interactions of the complexes 1 and 2 have been investigated by UV spectra, emission spectra and cyclic voltammogram. Concluding the results of three methods used to measure the interaction of complexes 1 and 2 with DNA, the action mode of the two complexes with DNA is intercalation, and character of ligands and steric effect may affect the interaction of the complexes with DNA.

A new manganeses(II) complex MnLCl2 · CH3OH (L = N,N′-bis(furaldehyde)diethylenetriamine) was synthesized and characterized by X-ray crystallographic analysis. The crystals are orthorhombic, space group Pnma with cell parameters a = 20.998(6), b = 13.314(5), c = 6.785(8) A, Z = 4, R 1 = 0.0609, and wR2 = 0.2116. The coordination geometry around Mn(II) atom is a trigonal-bipyramidic containing one tridenate ligand L and two Cl− ions.

In the title compound, [Cu2(CH3CO2)4(H2O)2]·2C11H6N2O, the dinuclear copper complex lies on a center of symmetry located midway between the two Cu atoms. The two Cu atoms are bridged by four acetate groups. The coordinated water mol­ecules interact with the C11H6N2O molecules and bridging acetate ligands by hydrogen bonds, giving rise to a linear chain structure.

The Zn atom in the title compound, [Zn(C11H6N2O)2(H2O)2](ClO4)2, lies on a center of symmetry in the crystal structure, and it is chelated by the heterocyclic ligands [Zn—O = 2.151 (4) and 2.276 (4) A]. The coordinated water mol­ecule interacts with the perchlorate ions to form a hydrogen-bonded layer structure. The compound is isomorphous with the Cu analog, whose structure has been detailed by Menon & Rajasekharan [Polyhedron (1998), 17, 2463–2476].

The Zn atom in the crystal structure of [Zn(C11H6N2O)2(H2O)2](NO3)2 lies on an inversion center; it is chelated by the 4,5-diazo­fluoren-9-one entity in a nearly isobidentate manner. The coordinated water mol­ecules link the nitrate anions to produce a linear hydrogen-bonded chain that runs along the a axis.