RESUMEN
The structure of the title complex, [Zn2(C2H3O2)4(C11H9N3O)2], is triclinic containing half of the mol-ecule in the asymmetric unit. Each zinc atom is coordinated to a pyridyl and oxime nitro-gen from one di-2-pyridyl ketone oxime (dpko) ligand and a third nitro-gen from the other dpko pyridyl ring. Additionally, each zinc is coordinated to two acetato anions, one of which is bidentate and the other monodentate. The uncoordinated oxygen of the monodentate acetato group is involved in a hydrogen bond with the oxime hydrogen. The packing in the crystal is assisted by weak C-Hâ¯O inter-actions between acetato groups and neighboring pyridyl rings.
RESUMEN
The crystal structure of the title compound, [Ni(C13H11N2O2)(H2O)4]Br3·2H2O, contains an octa-hedral NiII atom coordinated to the enol form of 1,3-di-pyridyl-propane-1,3-dione (dppo) and four water mol-ecules. Both pyridyl rings on the ligand are protonated, forming pyridinium rings and creating an overall ligand charge of +1. The protonated nitro-gen-containing rings are involved in hydrogen-bonding inter-actions with neighoring bromide anions. There are many additional hydrogen-bonding inter-actions involving coordinated water mol-ecules on the NiII atom, bromide anions and hydration water mol-ecules.
RESUMEN
The crystal structure of the title compound, [YbCl2(H2O)6]Cl, was determined at 110â K. Samples were obtained from evaporated aceto-nitrile solutions containing the title compound, which consists of a [YbCl2(H2O)6](+) cation and a Cl(-) anion. The cations in the title compound sit on a twofold axis and form O-Hâ¯Cl hydrogen bonds with the nearby Cl(-) anion. The coordination geometry around the metal centre forms a distorted square anti-prism. The ytterbium complex is isotypic with the europium complex [Tambrornino et al. (2014 â¶). Acta Cryst. E70, i27].
RESUMEN
New bimetallic complex salts corresponding to the formulation [Ni(L)][MCl(4)] have been synthesized by the facile reaction between [Ni(L)](ClO(4))(2) and [MCl(2)(PPh(3))(2)] in high yields [where M=Co(II), Zn(II), Hg(II) and L=3,7-bis(2-aminoethyl)-1,3,5,7-tetraazabicyclo(3.3.1)nonane]. The complexes were characterized by IR, electronic spectra, TGA/DSC, magnetic moment and conductivity measurements. The X-ray crystal structure for [Ni(L)][CoCl(4)] clearly establishes the cationic-anionic interaction. It crystallizes in the space group P1 with unit cell dimensions a=7.1740(15)A, b=8.1583(16)A and c=8.3102(16)A. A square-planar geometry is evident for the [Ni(L)](2+) cation while the anion is found to be tetrahedral. A two-step thermolytic pattern is observed in the pyrolysis of the bimetallic complex salts.
Asunto(s)
Magnetismo , Metales/química , Sales (Química)/química , Análisis Espectral/métodos , Cloruros/química , Cristalografía por Rayos X , Electroquímica/métodos , Modelos Moleculares , Estructura Molecular , TermodinámicaRESUMEN
The title complex, [Cu(C(11)H(10)N(2)O(2))(2)](BF(4))(2)·2H(2)O, was isolated as a dihydrate from a 1:2 molar mixture of copper(II) tetra-fluoridoborate hexa-hydrate with di-2-pyridyl ketone in aqueous solution. The centrosymmetric complex cation is structurally similar to that found in previously reported salts and exhibits Cu-O bonds deviating by 25 degrees from an octa-hedral geometry by the so-called 'off-axis angle' distortion. The BF(4) (-) anion exhibits a two site disorder of the fluorine atoms [ratio 0.210â (8):0.790â (8)].
RESUMEN
The title complex, [Cu(2)Br(3)(C(11)H(9)N(2)O(2))](n), was one of three isolated by slow evaporation of an acetonitrile reaction mixture of CuBr(2) with di-2-pyridyl ketone (1:1 molar ratio). The title complex contains a 2:1 metal-to-ligand ratio of copper(II) with the hydrated form of the ligand, di-2-pyridylmethane-diol. The two copper centers are bridged by a bromide ion and the alk-oxy O atom, and the Cu-Cu distance is 2.9801â (5)â Å. The dimeric units are further linked by bromide ions, leading to a two-dimensional extended bridged structure. O-Hâ¯O hydrogen bonds are present in the crystal structure.
RESUMEN
The centrosymmetric title complex, [Cu(2)Br(4)(C(11)H(10)N(2)O(2))(2)]·2H(2)O, was one of three complexes isolated by slow evaporation of an acetonitrile reaction mixture of CuBr(2) with di-2-pyridyl ketone (1:1 molar ratio). The title complex contains a 1:1 metal-to-ligand ratio of copper(II) with the hydrated form of the ligand di-2-pyridylmethane-diol. The copper centers are bridged by bromide donors, leading to a Cu-Cu distance of 4.090â (6)â Å. The crystals form as non-merohedral twins with two components related by a 180° rotation around the normal to [100]; the selected sample had a twin ratio of 0.63:0.37.
RESUMEN
The electronic structure of derivatives of VO(acac)(2) is probed using gas-phase UV-photoelectron spectroscopy [acac = 2,4-pentanedione]. The effect on the metal center of electron-donating and -withdrawing groups on the acac ligands is examined. Ionizations from metal-based, acac-based, and V=O-based orbitals are clearly observed. We find that changes at the ligand periphery lead to equivalent changes in the energies of the metal-based and ligand-based ionizations. Additionally, we find that a linear correlation exists between the ionization energies of the metalated complexes and the pK(a) values of the free ligands, indicating that the pK(a) is a good indication of the overall electron-donating abilities of acac ligands.