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Copper coordination complexes containing the 2‐methoxycarboxybenzoate (2‐mcob) ligand show different topologies depending on the nature of the dipyridyl coligand. [Cu2(2‐mcob)2(ebin)]n ( 1 ) [ebin = ethanebis(isonicotinamide)] shows a ladder structure based on anti‐syn bridged [Cu(OCO)]n chain motifs. [Cu2(2‐mcob)2(bbin)(H2O)2] ( 2 ) [bbin = butanebis(isonicotinamide)] displays a dimeric molecular structure. [Cu2(2‐mcob)2(hbin)]n ( 3 ) [hbin = hexanebis(isonicotinamide)] manifests a ladder structure very similar to that of 1 . {[Cu(2‐mcob)(dpa)] · H2O}n ( 4 ) [dpa = bis(4‐pyridyl)amine] shows a chain coordination polymer structure. All four materials showed significant promise as heterogeneous degradation catalysts for Congo Red dye in aqueous suspension under ultraviolet irradiation. Variable temperature magnetic susceptibility experiments for 1 indicated the presence of weak antiferromagnetic exchange (g = 2.059(2), J = –0.84(2) cm–1). Thermal degradation behavior is also discussed. 相似文献
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Hydrothermal synthesis has afforded a pair of isostructural acentric three-dimensional coordination polymers {[M2(malonate)2(dpa)(H2O)2] · 2H2O}n (M = Co, 1; M = Ni, 2; dpa = 4,4′-dipyridylamine), which were structurally characterized via single-crystal X-ray diffraction and spectroscopically and thermally analyzed. Both materials exhibit exotridentate malonate ligands conjoining metal atoms into grid-like [M(malonate)(H2O)]n layers; in turn, these are connected into 3-D sqp lattices (4466 topology) through tethering dpa ligands. The central kink and inter-ring torsion within the dpa ligands enforces the acentric Aba2 space group of crystals of 1 and 2. Antiferromagnetic coupling (g = 2.08(2), J = –1.05(8) cm−3) was observed within the malonate-bridged layer motifs within the cobalt derivative 1. In contrast, the nickel congener 2 exhibited ferromagnetic coupling (g = 2.201(1), J = 0.289(1) cm−3). 相似文献
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The hydrothermal reactions of MCl(2).6H2O (M = Co, Ni) NaVO3, 4,4'-dipyridylamine (dpa), and H2O yield materials of the type [M(Hdpa)2V4O12] (M = Co (1), Ni (2)). The two-dimensional structures of 1 and 2 are constructed from bimetallic oxide networks (MV4O12)n2n- with monodentate Hdpa projecting the protonated ring into the interlamellar region. The oxide network may be described as ruffled chains of corner-sharing (VO4) tetrahedra linked by (NiO4N2) octahedra into the two-dimensional assembly. Crystal data: C10H10Co0.5N3O6V2(1), monoclinic P2(1)/c, a = 10.388(1) A, b = 7.6749(7) A, c = 16.702(2) A, beta = 102.516(1) degrees, Z = 4. C10H10N3Ni0.5O6V2 (2), monoclinic, P2(1)/c, c = 10.3815(2) A, b = 7.7044(2) A, c = 16.6638(4) A, beta = 102.573(1) degrees, Z = 4. 相似文献
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Lindsey L. Johnston Joseph H. Nettleman Maxwell A. Braverman Laura K. Sposato Ronald M. Supkowski Robert L. LaDuca 《Polyhedron》2010
Three divalent copper coordination polymers containing aromatic dicarboxylate ligands and the long-spanning tethering imine bis(4-pyridylmethyl)piperazine (bpmp) have been prepared and structurally characterized. The length of the dicarboxylate pendant arms, carboxylate binding mode, and the inclusion of anionic components play a synergistic role in structure direction in this system. {[Cu(ip)(bpmp)(H2O)]·5H2O}n (ip = isophthalate, 1) displays neutral (4,4) rectangular coordination polymer grids that stack in an ABCD repeat pattern. Use of the longer pendant arm dicarboxylate 1,3-phenylenediacetate (phda) resulted in {[Cu2(phda)2(bpmp)]·H2O}n (2), a 3-D network coordination polymer with primitive cubic topology that features strongly antiferromagnetically coupled (J = −331(1) cm−1) {Cu2(CO2)4} paddlewheel units. In the presence of excess nitrate ions, {[Cu(phda)(Hbpmp)](NO3)·3H2O}n (3) was isolated instead of 2; 3 manifests cationic 2-D coordination polymer layers built from weakly antiferromagnetically coupled (J = −2.43(1) cm−1) {Cu2O2} dimers linked through phda and protonated bpmp ligands. The striking difference in magnetic properties is ascribed to the equatorial–equatorial versus axial–equatorial bridging of copper coordination spheres in 2 and 3, respectively. 相似文献
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The functional Ito formula, in the form df() = f( + d ) f(),is formulated and proved in the context of a Lie algebra L associatedwith a quantum (non-commutative) stochastic calculus. Here fis an element of the universal enveloping algebra U of L, andf() + d() f() is given a meaning using the coproductstructure of U even though the individual terms of this expressionhave no meaning. The Ito formula is equivalent to a chaoticexpansion formula for f() which is found explicitly. 1991 MathematicsSubject Classification: primary 81S25; secondary 60H05; tertiary18B25. 相似文献
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Reaction of divalent metal chlorides with succinic acid (H2suc) and the hydrogen-bonding capable tethering organodiimine bis(4-pyridylmethyl)piperazine (bpmp) in a mixed solvent system has afforded three isostructural coordination polymers: [M(suc)(bpmp)(H2O)2]n (M = Co, 1; M = Ni, 2; M = Cu, 3) Single-crystal X-ray diffraction showed that 1–3 possess [M(suc)(bpmp)(H2O)2]n 2D layer motifs. Parallel sets of layer motifs in 1–3 aggregate into 2d + 2d → 3D mutually inclined interpenetrated systems, fostered by hydrogen bonding interactions between layers. Spectral and thermal properties of these materials are also discussed. 相似文献