Search results for "Stoichiometry"
showing 10 items of 270 documents
NbxRu6-xTe8, New Chevrel-Type Clusters Containing Niobium and Ruthenium,
1996
Phases of composition Nb(x)()Ru(6)(-)(x)()Te(8) were prepared by reacting stoichiometric mixtures of the elements at high temperature in evacuated silica ampules. The structure of Nb(3.33)Ru(2.67)Te(8) was refined from X-ray powder data using the Rietveld method. Nb(3.33)Ru(2.67)Te(8) crystallizes isotypic with Mo(6)Q(8) (Q = S, Se, Te) in the rhombohedral space group Rthremacr; with the hexagonal lattice parameters a = 10.34106(5) Å, c = 11.47953(7) Å, and Z = 3. Its structure consists of M(6)Te(8) mixed-metal clusters (M = Nb, Ru) which are connected by intercluster M-Te bonds to form a three-dimensional network. Metal-metal bonding in these phases is analyzed in terms of Pauling bond ord…
Sr Doping and Oxygen Vacancy Formation in La1−xSrxScO3−δ Solid Solutions: Computational Modelling
2022
The study was performed with the financial support from the Latvian Council of Science under the grant agreement LZP-2020/2-0009. Calculations were performed at the HLRS, University of Stuttgart, within the project 12939 DEFTD. The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2.
Stoichiometric Control of the Magnetic Properties in Copper( II ) Cyano‐Bridged Bimetallic Complexes
2003
Control of the Cu2+ ion coordination environment affords a 1D, magnetically diluted compound, [Cu(cis-chxn)2]3[Fe(CN)6]2·7H2O (1) and the 2D ferromagnetic material [Cu(cis-chxn)]3[Fe(CN)6]2·6H2O (2) with a critical temperature, Tc, of 3.5 K. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Tuning the Spin Ground State in Heterononanuclear Nickel(II)−Copper(II) Cylinders with a Triangular Metallacyclophane Core
2010
3 páginas, 2 figuras, 1 gráfico.-- et al.
Tin(II) Derivatives of 2,3-Dihydroxynaphthalene
1983
Abstract The reaction of aqueous solutions of tin(II) chloride and 2,3-dihydroxynaphthalene (H2A) gives a white precipitate of SnA. This compound has been characterized by chemical analysis, IR spectra and thermogravimetric analysis. A spectrophotometric study of tin(II) and H2A in DMF shows the formation of two species with stoichiometric ratios Sn:H2A 1:1 and 1:2.
New Insights into the Stoichiometric and Catalytic Reactivity of Unsaturated Pd 3 (dppm) 3 CO n + Clusters ( n = 0, 1) Towards Halocarbons – First Ev…
2005
The title clusters, Pd 3 (dppm) 3 (CO) + and Pd 3 (dppm) 3 (CO) 0 can be electrochemically generated from the 1- and 2-electron reductions, respectively, of the Pd 3 (dppm) 3 (CO) 2 + cluster [dppm = bis(diphenylphosphanyl)methane; Pd 3 2 + ]. Pd 3 + reacts in a stoichiometric ratio with methyl iodide, MeI, and benzyl bromide, BzBr, in THF to provide the corresponding Pd 3 (X) + adducts (X = I, Br respectively) as inorganic products. Other products are Bz 2 and PhMe for BzBr but, for MeI, no organic product was observed (since they are too volatile). In the presence of the same substrates, Pd 3 0 also reacts in a stoichiometric ratio to form the same organics and the Pd 3 -(X) + adducts (X …
Phenolate complexes of iron(III) in dimethylsulphoxide solution
1984
The formation of complexes between Fe3+ and 2,4-dinitrophenol, 4-nitrophenol and 4-methylphenol is studied in dimethylsulphoxide solution. The reaction proceeds almost to completion and the occurrence, in solution, of complexes with higher stoichiometry than 1∶1 is reported for the first time. The following stability constants are determined (25 °C, 0.1 M KClO4): FeIII-2,4-dinitrophenolate β1=1.8×103, β2=4.4×105; FeIII-4-nitrophenolate β1=1.10×107, β2=2.5×1012 β3=3.9×1016; FeIII-4-methylphenolate β=1.7×1012.
Tungsten(VI) complexes formed in an excess of gluconic acid: A polarimetric and spectrophotometric study
1985
The tungsten(VI)-gluconic acid system in an excess of this organic reagent has been spectroscopically and polarimetrically studied and four species, two mononuclear with stoichiometry 1∶2 (metal∶ligand) and two dinuclear with composition 2∶2, have been identified. The non-formation of a binuclear species with stoichiometry 2∶1 (metal∶ligand) demonstrates some preference towards coordination of carboxylate group.
Pd/Co3O4 catalyst for CH4 emissions abatement: study of SO2 poisoning effect
2007
A catalyst with 0.7 wt% Pd load supported over Co3O4 oxide was investigated in the methane oxidation by operating under CH4/O2 stoichiometric conditions. The effect of the noble metal addition on the activity of bare Co3O4 was evaluated. Samples were characterized by BET, XRD, TPR and XPS analyses. The SO2 poisoning of Pd catalyst and Co3O4 was studied by performing CH4 oxidation tests under stoichiometric conditions in SO2 (1 ppm or 10 ppm). Experiments evidenced that in our conditions the low amount of SO2 doesn’t influence the Pd behaviour, whereas in presence of 10 ppm of SO2 some deactivation occurs that becomes more evident above 450 °C at which the catalyst doesn’t reach 100% of meth…
Bismuth trihalide complexes with nitrogen and phosphorus chelating ligands
1985
Abstract Bismuth(III) halides react with 1,10-phenanthroline, 2-pyridinecarboxaldehyde-2-pyridylhydrazone and diphenylphosphynoethane in methanol. A stoichiometry differing from 1:1 is found only for BiCl 3 (Phen) 1.33 and BiCl 3 (Dpe) 1.5 . Characterization of these compounds, which are not very soluble in common solvents, follows from analytical, mass and IR spectral data. In the low frequency region, the IR spectra proved to be useful to ascertain the presence of bridging halogens.