Search results for "Metallic"
showing 10 items of 813 documents
A Novel One-Dimensional Cyano-Bridged Ni3Fe2 Ferromagnet Constructed from Bimetallic Molecular Squares
2003
Reaction of the complex [Ni(rac-CTH)](2+) (rac-CTH = rac-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) with [Fe(CN)(6)](3-) leads to a novel cyano-bridged Ni(3)Fe(2) complex, [[Ni(rac-CTH)](3)[Fe(CN)(6)](2)](4). The structure consists of an alternating arrangement of [Fe(CN)(6)Ni(rac-CTH)](2) squares and trans-planar [Ni(rac-CTH)](2+) units bridged by cyanide groups to give a neutral 1D chain running along the a axis. Magnetic measurements reveal the occurrence of ferromagnetic coupling between Fe(III) and Ni(II) ions and 3D magnetic ordering at 3 K due to interchain interactions. Canting of the moments is inferred from the low value of the magnetization of the saturation bel…
Modulating magnetic dynamics through tailoring the terminal ligands in Dy2 single-molecule magnets
2020
Complexation of dysprosium(III) ions with a multidentate hydrazone ligand, N-[(E)-pyridin-2-ylmethylideneamino]pyridine-2-carboxamide (L), in the presence of different β-diketonate coligands, leads to the formation of two novel DyIII dimers, with formulas Dy2(BTFA)4(L)2 (1) and Dy2(TTA)4(L)2 (2) (BTFA = 3-benzoyl-1,1,1-trifluoroacetone and TTA = 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionate). They exhibit slightly different coordination geometries around DyIII centers and discrepant binuclear motifs – as a result of altering the β-diketonate coligands – which has an impact on the magnetic interactions between metal centers, the local tensor of anisotropy on each DyIII site and their relat…
Gold catalysis in southern Italy
2009
The First P ‐Stereogenic 1D Coordination Polymers with the Metal Centers in the Backbone
2011
The enantiomeric ligands (R,R)- and (S,S)-bis(o-anisylphenylphosphanyl)methane (R,R-22 and S,S-22) and (R,R)- and (S,S)-bis(phenyl-m-xylylphosphanyl)methane (R,R-23 and S,S-23; dppm*), were treated with [Cu(NCCH3)4](BF4) and AgBF4 to produce the binuclear complexes [Cu2(dppm*)2(NCCH3)4](BF4)2 or [Ag2(dppm*)2](BF4)2, respectively. Then, these complexes were used as building blocks to prepare the first P-chirogenic 1D coordination polymers {[M2(dppm*)2(dmb)2](BF4)2}n [dppm* = (R,R)-22, (S,S)-22, (R,R)-23, (S,S)-23, M = Cu, Ag, dmb = 1,8-diisocyano-p-menthane] where M is part of the backbone of the polymer chain. The isostructural nature of these new polymers with the achiral parent polymers, …
Synthesis, characterization and a voltammetric study of (Bu4N)2[Mo2Br6]. Oxidation-reduction mechanism of related compounds
1984
The synthesis and characterization of (Bu4N)2[Mo2Br6], obtained from Mo(CO)6, (Bu4N)Br and 1,2-dibromoethane, is described. The electrochemical behaviour of [Mo2Br6]−2 and related species is studied, and an oxidation-reduction mechanism is proposed.
One-dimensional and two-dimensional anilate-based magnets with inserted spin-crossover complexes.
2014
The syntheses, structures, and magnetic properties of a family of bimetallic anilate-based compounds with inserted spin-crossover cationic complexes are reported. The structures of 1-4 present a two-dimensional anionic network formed by Mn(II) and Cr(III) ions linked through anilate ligands with inserted [Fe(III)(sal2-trien)](+) (1), [Fe(III)(4-OH-sal2-trien)](+) (2), [Fe(III)(sal2-epe)](+) (3), or [Fe(III)(5-Cl-sal2-trien)](+) (4) complexes. The structure of 5 is formed by anionic [Mn(II)Cl2Cr(III)(Cl2An)3](3-) chains surrounded by [Fe(II)(tren(imid)3)](2+), Cl(-), and solvent molecules. The magnetic properties indicate that 1-4 undergo a long-range ferrimagnetic ordering at ca. 10 K. On t…
Photochemical Synthesis and Reactivity of New Chloro-Bridged Complexes with Tungstenocene (η5-C5H5)(η5-C5H4PPh2)WClX (X = H, Cl) and Tetracarbonylmet…
1999
Chloro-bridged bimetallic complexes (η5-C5H5)[η5-C5H4PPh2M′(CO)4]W(μ-Cl)X [X = Cl (3), × = H (4); M′ = Cr, W] were prepared by photochemical irradiation of (η5-C5H5)[η5-C5H4PPh2M′(CO)5]WClX [X = Cl (1), × = H (2); M′ = Cr, W]. The reactivity of the chloro-bridged complexes towards Lewis bases was studied; by exposure to CO or phosphanes, a facile cleavage of the chloro bridge accompanied by regio- and stereospecific coordination at M′ occurs. The X-ray structure of complex 3 (M′ = W) is reported.
Complexes of organometallic compounds
1974
Abstract Tetraphenylarsonium and tetramethylammonium salts of the complex anions Ph 3 Pb(N 3 ) − 2 , Ph 3 Pb(N 3 )(NCS) − , Ph 2 Pb(N 3 ( 2 − 4 )) and Ph 2 Pb(N 3 )(NCS) − 2 have been prepared and characterized. Infrared spectra and solution conductance data are reported. Possible configurations of the complex anions are discussed.
Monitoring the carburization of molybdenum bimetallic nitrides and oxynitrides with CH4/H2/Ar mixtures: identification of a new carbonitride.
2008
A new carbonitride Ni2Mo3(CxNy) has been synthesized by temperature-programmed carburization of the Ni2Mo3N precursor with a CH4/H2/Ar gas mixture at 923 K. This compound has been characterized by X-ray diffraction, elemental analysis, Auger electron spectroscopy, laser Raman spectroscopy, thermogravimetric analysis and field-emission scanning electron microscopy. Ni2Mo3(CxNy) crystallizes in the cubic space group P4(1)32, with a lattice parameter of a=6.64575(3) A, corresponding to the unusual filled beta-Mn structure. Its formation occurs by partial substitution of N by C via a topotactic and pseudomorphic reaction and its stability in air is higher that of Ni2Mo3N. A two-phase mixture wi…