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Selective bond formation with the series of first-period transition metal ions is accomplished using the metalloligand L(super Cu) [Cu(2,4-pydca)(sub 2)](super 2-). New Cu(super II) metalloligand [Cu(2,4-pydca)(sub 2)](super 2-) L(super Cu) controlled bond formation for the first-period transition metal ions and magnetic properties.

The synthesis of a new copper(II) coordination polymer Cu(sub 2)(oxalate)(sub 2)(pyrazine)(sub 3)n reveals the crystallographic structure of the copper (II) units. The coordination polymer crystallizes in the triclinic space group and displays an extended sheet structure of copper(II) ions joined by oxalate anions and pyrazine. The recurring unit of the polymer contains two types of 4 + 2 coordination systems with O4N2. The Cu-ox-Cu-arrangement demonstrates a pleated ribbon, which shows that the planes of Cu-ox-Cu form a boat conformation.

A report that MX-chain complex [NiBr-(chxn)2]Br2 is different from the charge-density-wave (CDW) complexes is presented. In this complex, an unpaired electron in the Ni(super 3+)3d(sub z)2 orbital is strongly localized on the Ni atom owing to the strong electron correlation.

The synthesis, crystal structure, and physical properties of a mixed-valence coordination polymer, {[Cu(super I)(sub 4) Cu(super II)(Et2dtc)2Cl3][Cu(super II)(Et2dtc)2]2(FeCl4)}(sub n)(Et2dtc(super )-=diethyldithiocarbamate) displaying two-dimensional ferromagnetic structural order are described. The complex is synthesized by a reaction of a CHCI3 solution of (Et2dtc)3 and acetone solution of CuCl2.2H20.

Investigates the synthesis of the copper(II) coordination polymer, [Cu2(mu-ox)2(mu-pyz)(pyz)2]n (ox = oxalate, pyz = pyrazine). Crystallographic structure; Measurement of magnetic susceptibilities; Analysis using an alternating-chain Heisenberg-exchange model.

The reaction of Cu(Hm-dtc)2, Br2, and CuBr2 yielded a new mixed-valence octanuclear CuI/CuII/CuIII cluster, encapsulating a Br anion in the center of the cluster cage. The octanuclear cluster units form a 1D assemblage, which induces intervalence charge-transfer transitions from CuII ions to CuIII ions between the clusters. [ABSTRACT FROM AUTHOR]

New mixed-valence CuI—CuII coordination polymers with one-dimensional, infinite-chain structures, [CuI2CuIIX2(Hm-dtc)2(CH3-CN)2]n [Hm-dtc- = hexamethylene dithiocarbamate; X = Br (1), I- (2)], have been prepared and structurally characterized by X-ray diffraction. These complexes consist of a mononuclear copper(ll) unit CuII(Hm-dtc)2 and dinuclear copper(l) units CuI2(CH3CN)2X2. Magnetic studies have revealed that these complexes have a relatively strong antiferromagnetic interaction [J = -26.9 cm-1 (1) and J = -22.2 cm-1 (2)] between the unpaired electrons of the CuII ions through the dinuclear copper(l) halide unit of CuI2X2 in the chain. The electrical properties of 1 and 2 are investigated using an impedance spectroscopy technique, and it is revealed that these complexes exhibit intriguing semiconducting properties with small activation energies [Ea = 0.562 eV (1) and Ea = 0.479 eV (2)]. [ABSTRACT FROM AUTHOR]

The article reports that extensive research has been devoted to the synthesis of coordination polymers with characteristic physical and/or chemical properties, including magnetism conductivity, nonlinear optical responses catalysis, gas storage, and ion exchange. Studies of mixed-valence coordination polymers are less developed in comparison of conventional homo-valent coordination polymers because of synthetic challenges, despite the potential for new functional materials based on the occurrence of inter-valence charge transfer. The diversity of the spin states, and the availability of versatile frameworks, like I-D halogen-bridged complexes, and a dithiooxalate-bridged iron polymer.

In the field of solid-state chemistry and physics, there is much interest in one-dimensional (1-D) electron systems because pronounced phenomena characteristic of 1-D systems have been observed such as the Haldane gap in integer spin antiferromagnetic compounds, solitons and polarons observed in ru-conjugated polymers, slow relaxation of magnetization in several ferromagnetic and ferrimagnetic compounds known as single-chain-magnets. Halogen-bridged 1-D metal complexes (MX-chains) also have been attractive targets because of the highly isolated 1-D chain structure and the variety of the electronic states which can be tuned by substituting those components. MX-chain complexes with a mixed-valence structure have been widely studied as 1-D materials with strong electron-lattice interactions.

Halogenation of organic compounds is one the most important transformations in chemical synthesis and is used for the production of various industrial products. A variety of halogenated bisphenol analogs have recently been developed and are used as alternatives to bisphenol A (BPA), which is a raw material of polycarbonate that has adverse effects in animals. However, limited information is available on the potential toxicity of the halogenated BPA analogs. In the present study, to assess the latent toxicity of halogenated BPA analogs, we evaluated the binding and transcriptional activities of halogenated BPA analogs to the estrogen-related receptor γ (ERRγ), a nuclear receptor that contributes to the growth of nerves and sexual glands. Fluorinated BPA analogs demonstrated strong ERRγ binding potency, and inverse antagonistic activity, similar to BPA. X-ray crystallography and fragment molecular orbital (FMO) calculation revealed that a fluorine-substituted BPA analog could interact with several amino acid residues of ERRγ-LBD, strengthening the binding affinity of the analogs. The ERRγ binding affinity and transcriptional activity of the halogenated BPAs decreased with the increase in the size and number of halogen atom(s). The IC 50 values, determined by the competitive binding assay, correlated well with the binding energy obtained from the docking calculation, suggesting that the docking calculation could correctly estimate the ERRγ binding potency of the BPA analogs. These results confirmed that ERRγ has a ligand binding pocket that fits very well to BPA. Furthermore, this study showed that the binding affinity of the BPA analogs can be predicted by the docking calculation, indicating the importance of the calculation method in the risk assessment of halogenated compounds.

A new semiconducting 3D coordination polymer, [Cu 2 Br 2 (ttz)] n (1), with an acceptor bridging ligand, 1,2,4,5-tetrazine (ttz), was synthesized. The complex shows large absorption bands extending to the near-IR region, indicating a small band gap in the coordination polymer. This complex shows higher conductivity than those of [CuBr(pyz)] n (2), including pyrazine (pyz) with a higher lowest unoccupied molecular orbital level. We performed density functional theory band calculations using the VASP program to understand the electronic states and conducting paths of the coordination polymer.

The establishment of technology for rapid and complete removal and mineralization of harmful phenolic compounds from water is of great importance for environmental conservation. Visible-light irradiation (λ > 430 nm, light intensity integrated from 420 to 485 nm = 6.0 mW cm -2 ) of Au nanoparticle (NP)-loaded TiO 2 (Au/TiO 2 ) in dilute aqueous solutions of bisphenol A (BPA) and p-cresol (PC) causes degradation of the phenols. The addition of trimethylstearylammonium chloride (C 18 TAC) enhances the adsorption of BPA on Au/TiO 2 to greatly increase the rate of reaction. Consequently, 10 μM phenols are completely removed from the solutions within 2.5 h irradiation, and prolonging irradiation time to 24 h quantitatively oxidizes BPA to CO 2 . Dynamic light scattering ζ-potential measurements indicate that a C 18 TAC bilayer or admicelle is formed on the Au/TiO 2 particle surface at C 18 TAC concentration >50 μM. The action spectrum for reaction shows that this reaction is driven by the Au NP localized surface plasmon resonance excitation-induced interfacial electron transfer from Au to TiO 2 . We propose a possible reaction scheme on the basis of the experimental results including intermediate analysis.

The reaction of Cu(Hm-dtc)(2), Br(2), and CuBr(2) yielded a new mixed-valence octanuclear Cu(I)/Cu(II)/Cu(III) cluster, encapsulating a Br anion in the center of the cluster cage. The octanuclear cluster units form a 1D assemblage, which induces intervalence charge-transfer transitions from Cu(II) ions to Cu(III) ions between the clusters.

The first mixed-valence coordination polymer indicating ferroelectric properties, {[CuI4CuII(Et2dtc)2Cl3][CuII(Et2dtc)2]2(FeCl4)}n (Et2dtc- = diethyldithiocarbamate), has been synthesized and crystallographically characterized. This complex has a two-dimensional infinite square lattice structure, including both Cu(I) and Cu(II) ions, which is confirmed by XPS and SQUID measurements. In addition, the ferroelectric behaviors are revealed by the dielectric measurements with a LCR meter and a ferroelectric tester.

[structure: see text] A novel TTF-based donor with a uracil moiety, TTF-(1-n-butyluracil-5-yl) (TnbU), was synthesized. Crystal structures of both TnbU and the charge-transfer complex of TnbU-hydrogen cyananilate possess complementary double hydrogen bonds through uracil moieties and pi-stacking dimer structures between TTF skeletons. Furthermore, the TnbU-TCNQ charge-transfer complex shows a high electrical conductivity underlying the partial charge-transfer accompanied by a hydrogen-bonding interaction, which was substantiated in terms of the measurements of the IR, electronic spectra, and conductivity.