The title salt, [CoBr(C11H27N5)]Br2·2H2O, contains a complex cation with mirror symmetry and two Br(-) counter-anions that are likewise located on the mirror plane. The central Co(III) atom of the complex cation has one Br(-) ion in an axial position, one N atom of the penta-dentate macrocyclic ligand in the other axial position and four N atoms of the ligand in equatorial positions, defining a...

The new [Co(Salen)(PBu3)2]ClO4, [Co(Salen)(PBu3)2]BF4, [Co(Salpn)(PBu3)2]ClO4 and [Co(Salen)(PMe2Ph)2]ClO4 ( where salen = bis(salisylaldehyde)ethylenediimine)) complexes were synthesiszed and chracterized by IR, UV-Vis, 1H NMR spectroscopy and elemental analysis. The IR and 1H NMR spectra cofirmed that the synthesised complexes contain Schiff base ligand, phosphane and conter ion and the eleme...

Fe(III) (oxyhydr)oxides affect the mobility of contaminants in the environment by providing reactive surfaces for sorption. This includes the toxic metal cadmium (Cd), which prevails in agricultural soils and is taken up by crops. Fe(III)-reducing bacteria can mobilize such contaminants by Fe(III) mineral dissolution or immobilize them by sorption to or coprecipitation with secondary Fe mineral...

In this study, mononuclear octahedral cobalt(III) Schiff base complex [CoL3], L = (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine, was synthesized from the reaction of Co(NO3)2•6H2O and the Schiff base ligand L in methanol as solvent. It used as a new precursor to prepare spinel type cobalt oxide nanoparticles by a facile solid-state thermal decomposition. Controlling the temperature and time, Co3...

The possibility of hydroxylamine electrochemical determination over a CoO(OH)-modified electrode, accompanied by complex-formation, has been studied from the theoretical point of view. The correspondent mathematical model has been developed and analyzed by means of linear stability theory and bifurcation analysis. It was shown that CoO(OH) may be applied as an efficient electrode modifier i...

The pendent-arm macrocyclic hexaamine trans-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine (L) may coordinate in tetra-, penta- or hexadentate modes, depending on the metal ion and the synthetic procedure. We report here the crystal structures of two pseudo-octahedral cobalt(III) complexes of L, namely sodium trans-cyano(trans-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-d...

In an attempt to synthesize new cobalt(II) sulfate framework structures using 1,4-diaza-bicyclo-[2.2.2]octane as a template, crystals of poly[0.35-[hexa-aqua-cobalt(II)] [tri-μ-hydroxido-μ-sulfato-dicobalt(II)]], {[Co(H(2)O)(6)](0.35)[Co(2)(OH)(3)(SO(4))]}(n), were obtained as a mixture with [Co(H(2)O)(6)]SO(4) crystals. The crystal structure can be described as being constructed from discrete ...

The objective of this study is to develop a simple, environmentally benign alternate analytical method for simultaneous estimation of iron oxidation states. This proposed method of iron speciation is based on 1,10-phenanthroline (phen) modified redox potential of transition metal ions. In a pre-step excess cerium(IV) oxidizes iron(II) in sample to iron(III). Initial back titration of un-reacted...

Exploiting carbon dioxide as co-monomer with epoxides in the production of polycarbonates is economically highly attractive. More effective catalysts for this reaction are intensively being sought. To promote better understanding of the catalytic pathways, this study uses density functional theory calculations to elucidate the reaction step of CO2 insertion into cobalt(III)-alkoxide bonds, whic...

1. The preparation of a crude extract of Clostridium tetanomorphum containing cobalt porphyrin synthase but little haem-synthase activity is described. 2. The properties of cobalt porphyrin synthase in the clostridial extracts is compared with the properties of a haem synthase present in crude extracts of the yeast Torulopsis utilis. 3. Cobalt porphyrin synthase in extracts of C. tetanomorphum ...