A novel 2D coordination polymer [Zn2(bim)4]n(1)(Hbim=benzimidazole) based on dihydrated-[N,N'-bis(2-aminophenl)-oxalamide](L1·2H2O) with zinc nitrate has been synthesized.Previously we have synthe-sized complexes [In2Zn3(im)12]n(2)(Him= imidazole) and [Zn(im)2]n(3) successfully.In complex 1,each Zn(Ⅱ) coor-dinated with four ligands adopts a distorted tetrahedron coordination mode,and the 2D grid structure is built by the Zn(bim)4 as the secondary building unit(SBU).The luminescence properties of the three complexes were investigated for the first time.The emissions with maxima for complexes 1,2 and 3 are at 379,469 and 392 nm,respectively.
A novel three-dimensional(3D) supramolecular architecture, {[Nd(OH-BDC)(OH-HBDC)(H2O)2]·2H2O}n (1) (OH-H2BDC=5-hydroxyisophthalic acid), which was formed through hydrogen bonds and π-π stacking between two-dimensional(2D) layers, was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Windmill building blocks, which consist of two nine-coordinated metal centers and four OH-H2BDC groups are connected through two carboxyl groups, to lead to a one-dimensional infinite inorganic chain(···M―O―C―O―M···) along the [100] direction. An observed intense blue luminescence with an emission band peaked at 390 nm for compound 1 may results from ligand-to-metal charge transfer(LMCT). Variable-temperature magnetic susceptibility of compound 1 was investigated and the value was deviated from the Curie-Weiss law.
YU Li-qiong HUANG Ru-dan CHI Ying-nan HU Chang-wen
The title complex, [[Cd(Him)(OH-BDC)(H2O)2]·3H2O]n (1) (Him is imidazole, OH-H2BDC is 5-hydroxyisophthalic acid), was synthesized by liquid/liquid diffusion method at room temperature. The complex crystallizes in orthorhombic, space group P212121, with a=0.671 6(7), b=1.380 6(2), c=1.742 1(2) nm, V=1.615 2(3) nm3, C11H18CdN2O10, Mr=450.67, Dc=1.853 g/cm3, μ=1.407 mm-1, F(000)=904, Z=4, the final R1=0.020 9 and wR2=0.045 3 for 3 211 observed reflections (I>2σ(I)). In the structure of 1, the OH-BDC ligands exhibiting bis-bidentate coordination mode bridge the adjacent Cd centers to form a one-dimensional helical chain and the second ligand Him acting as terminal ligands are attached to the helical chain. It is notable that a series of complicated hydrogen bonds (e.g., N—H…O, O—H…O) exist in the structure, which link neighboring helices into a three-dimensional supramolecular architecture. An observed intense blue luminescence with an emission band peaking at 390 nm for 1 may be resulted from ligand-to-metal charge transfer (LMCT).
Three new Keggin polyoxometalates, [Zn(phen) 3 ] 2 [SiW 12 O 40 ]·5H 2 O(1), [Co(phen) 3 ] 2 [SiW 12 O 40 ](2) and [Ni(phen) 3 ] 2 [SiW 12 O 40 ]·2H 2 O(3)(phen=1,10′-phenanthroline) have been hydrothermally synthesized and characterized by elemental analysis, IR, crystal X-ray diffraction, thermogravimetric analyses(TGA) and fluorescence techniques. Complex 1, crystallized in the triclinic space group P1, consists of one [SiW 12 O 40 ] 4– anion, two discrete [Zn(phen) 3 ] 2+ cations and five crystal water molecules. Complexes 2 and 3 have the similar configuration to complex 1, but they crystallized in the monoclinic space group C2/c. Variable-temperature magnetic susceptibilities of complexess 2 and 3 reveal antiferromagnetism and ferromagnetism, respectively.
ZHANG Yong-feng JIA Yan-yan NIE Hai-liang YAN Xing-juan WANG Li HUANG Ru-dan
Introduction In recent years,considerable attention has been paid to supramolecular networks based on metal organic building blocks because of their potential applications in diverse fields,such as,catalysis,optics,sensors, magnetism,and molecular recognition[1-3].On the ba-
