Materials Literature
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Copper(II) 3',4'-bis(N,N'-oxamato)terthiophene has been synthesized and electropolymerized. The copper(II)-complex centers are not affected by the polymerization process, which involves coupling between Calpha carbon atoms of the terthiophene units and leads to a new conjugated polymer consisting of polythiophene chai…
Binary metal imidazolates of the group 10 metals have been prepared and typically found amorphous. However, the intermediacy of a number of (poly)crystalline species during their formation has been evidenced; their selective preparation and characterization, by chemical, spectroscopic, and thermal methods and their st…
Abstract Copper(II), nickel(II), cobalt(III) and iron(III) complexes of D ‐glucosamine, and their complexes with α‐glycine were synthesized. The eight novel metal complexes were characterized by means of IR, electronic absorption and 1 H NMR spectroscopy. The surface‐enhanced Raman scattering (SERS) spectra of these c…
Evidence for an unusual double charge disproportionation, Mn 4+ + Co 2+ → Mn 3+ + Co 3+ → Mn 4+ + Co 2+ , is observed in nanocrystalline LaMn 0.5 Co 0.5 O 3 synthesized by a low-temperature method and annealed in the temperature range 200–1300 °C. The Curie temperature of nanocrystalline LaMn 0.5 Co 0.5 O 3 is increas…
The influence of pressure on the crystal structure of LaGaO 3 has been studied using synchrotron x-ray diffraction. At atmospheric pressure LaGaO 3 has an orthorhombic structure in Pnma and undergoes a first-order phase transition to a rhombohedral structure near 2.5 GPa. The transition is reversible and the orthorhom…
We report O and Ca K-edges x-ray absorption near edge structure (XANES) spectra of Ba 1- x Ca x TiO 3 ( x = 0.01 and 0.08), BaTiO 3 and CaTiO 3 and the electronic structure of Ba 0.875 Ca 0.125 TiO 3 obtained by first-principles calculation. The characteristic features in the O K-edge XANES spectra of these ferroelect…
Fitting B2 bridges in porphyrins (see picture) can be achieved by reaction of dilithiated porphyrins with B2Cl4 as well as by reductive elimination from diborylporphyrins. Coordination takes place under rectangular distortion of the porphyrin framework.
Both the low (γ)- and high (γ′)-temperature polymorphs of Bi2MoO6 are oxide ion conductors. The γ′ conductivity at 300 °C is comparable to that of yttria-stabilized zirconia (YSZ) while its activation energy, 0.510(2) eV, is much less than that of YSZ, 0.79 eV, and is lower than that of the best low temperature oxide…
The alignment of liquid crystals through magnetism demands a high value of the magnetic anisotropy. The magnitude of the anisotropy for a series of isostructural lanthanide-containing metallomesogens can be estimated on basis of the crystal-field splitting of the (7)F1 multiplet in the corresponding europium(III) comp…
Reaction of (NH4)2[WS4], [Ag(MeCN)4](PF6) and dppm (molar ratio = 1∶2∶4) in the solid state at 110 °C followed by extraction with CH2Cl2 yielded a hexanuclear neutral cluster [(WS4)2Ag4(dppm)3] 1, while the same materials when mixed directly in CH2Cl2 produced a tetranuclear cluster salt [WS4Ag3(dppm)4](PF6) 2; both c…
Almost linear I-Se-Br groups with d(Se-Br)>d(Se-I) occur in 1⋅2 IBr, the first "T-shaped" Se adduct with IBr, which was synthesized by the oxidative addition of IBr to 1,2-bis(3-methylimidazoline-2-selonyl)ethane (1) in MeCN. Density functional theory calculations indicate the intramolecular Br⋅⋅⋅H interactions as bei…
High specific surface areas and adjustable pore sizes are outstanding characteristics of nanoporous silicon nitride based materials prepared by using oxygen-free molecular precursors in a novel template-assisted sol-gel approach. The nitrides represent a new class of shape-selective superbase catalysts (see, for examp…
The tripodal ligand (alpha,alpha',alpha' 'nitrilotri(6-methyl-2-pyridinecarboxylic acid)) (H(3)tpaa) forms a Gd(III) complex which has a relaxivity (r(1p) = 13.3 mM(-1) s(-1) at 25 degrees C and at 60 MHz) remarkably higher than those of the currently clinically used contrast agents based on octacoordinate polyaminoca…
A bis-chelating ligand (L1), made of two 7-(p-anisyl)-1,10-phenanthroline (phen) subunits connected with a p-(CH(2))(2)C(6)H(4)(CH(2))(2) spacer through their 4 positions, has been prepared, using Skraup syntheses and reaction of the anion of 4-methyl-7-anisyl-1,10-phenanthroline with alpha,alpha'-dibromo-p-xylene. It…
The self-complementary coordination unit [Cu(H2sabhea)]+ with a pentadentate amino alcohol as ligand enables the synthesis of the first triply hydrogen-bridged dinuclear copper(II) complex (see picture). Proton transfer allows the reversible transformation between this triply and the corresponding doubly hydrogen-brid…
The structure of (1- x )[Pb(Mg 1/3 Nb 2/3 )O 3 ]- x PbTiO 3 is tetragonal and rhombohedral for x ⩾0.35 and x ⩽0.30, respectively. The intrinsic width of the morphotropic phase boundary region (0.30< x <0.35) is an order of magnitude smaller than hitherto believed. The structure of the morphotropic phase for x = 0.34 i…
Through a simple gas reaction, single-crystalline β-Ga 2 O 3 nanoribbons, nanosheets and nanowires were synthesized on a large scale at 700 °C. They were characterized by means of x-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive x-ray spectroscopy (EDS), transmiss…
Self-aggregation of water-soluble pyridinium-substituted porphyrins with functionalized calixarenes leads to well-defined pH-tunable stoichiometries. Two assemblies with different porphyrin:calixarene ratios that crystallized at pH 2 and 6 have been structurally characterized. The Job plots of Soret band broadenings i…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTFirst Unequivocal Observation of the Whole Bell-Shaped Energy Gap Law in Intramolecular Charge Separation from S2 Excited State of Directly Linked Porphyrin−Imide Dyads and Its Solvent-Polarity DependenciesNoboru Mataga, Haik Chosrowjan, Yutaka Shibata, Naoya Yoshida,…
complex of an N-alkyloxysalicylidenyl-N'-ethyl-N-ethylenediamine ligand, shown as a computer model in the picture, is the first compound in which spin-crossover (SC) and liquid-crystalline (LC) properties coexist. This synergy should allow the magnetic and optical properties of SC compounds to be combined with the sen…