Electron spin resonance spectra of copper(II) bipyridyl complexes

Monodentate coordinated chromate(VI) ion in [Cu(phen)2OCrO3](phen)0.5·4H2O completing the square pyramidal geometry of the copper(II) in the solid state

“…:bpy = 1:2 exhibit disproportionation to the 1:1 and 1:3 species and the parameters g k = 2.266, g \ = 2.070, A k = 181 9 10 -4 cm -1 corresponding to [Cu(bpy) 3 ] 2? complex [55,56] are practically identical with those observed for the spectrum of 1 in formamide. It supports additionally the conclusion drawn on the basis of electronic studies that [Cu(phen) 3 ] 2?…”

Sorption–catalytic testing of copper on a paper-based sorbent with attached alkylamino groups

“…1(b)-(d)] allowed us to select the optimum conditions of the indicator reaction on HMDA filters (8 3 10 27 mol hydroquinone, 9 3 10 26 mol H 2 O 2 and 1 3 10 27 mol dipy). The curves of reaction rate on HMDA filters versus concentration of the reagents feature either a maximum or a plateau similar to the main properties of the curves obtained in solution, 4,5 which indicates that the reaction on HMDA filters involves the formation of a catalytically active intermediate complex of Cu II with the reagents analogous to that proposed for this reaction in solution 10,12 and probably including the nitrogen atoms of HMDA.…”

Spectral and electrochemical studies of bis(diimine)copper(II) complexes in anionic, cationic and nonionic micelles

“…The complex cations [Cu(bpy) 2 Cl] + [40,43] and [Cu(phen) 2 Cl] + [44][45][46][47][48][49][50], possess a distorted trigonal bipyramidal geometry in which the trigonal plane is composed of copper(II) bound to two nitrogen atoms, one each from the two diimine ligands, and a chloride ion and the axial positions are occupied by the remaining two diimine nitrogen atoms. The related complexes [Cu(4-Me-phen) 2 Cl] + , [Cu(5-Me-phen) 2 Cl] + and [Cu(4-NO 2 -phen) 2 Cl] + are expected to possess a coordination geometry similar to that of [Cu(phen) 2 [54][55][56] to display a tetragonally distorted octahedral geometry in which the corners of the square plane are occupied by one nitrogen atom each of the two diimine ligands, a chloride ion and water and the axial positions by the remaining two nitrogen atoms of the diimines. The related cations [Cu(4-Me-phen) 2 [52] to possess a trigonal bipyramidal coordination structure, and the copper(II) complexes of the related ligands 4,7-dmp and 3,4,7,8-tmp are expected to have a similar coordination geometry in the solid state.…”

“…The complex cation [Cu(dpq) 2 Cl] + with a trigonal bipyramidal coordination geometry is expected to exist as [Cu(dpq) 2 (H 2 O)Cl] + species in aqueous solution. Electronic and EPR spectral techniques have been employed to diagnose the coordination geometries of the complexes in aqueous solution [54][55][56]. While the bpy and phen complexes have been suggested to assume a cis-octahedral symmetry, the 2,9-dmp complex possesses a distorted square pyramidal geometry.…”

“…The cyclic voltammetric (CV) and differential pulse voltammetric (DPV) results for the complexes 1-10 in aqueous and aqueous micellar solutions are summarized in Tables plot passing through the origin suggests that the redox couple tends to become diffusion controlled; however, the deviation of the values of i pa /i pc (0.7-1.6) and the peak potential separation (DE p ) from unity and 59 mV respectively expected for a one electron diffusion controlled reversible redox process indicate that the redox behavior is far from reversible [54,55]. The shape of the plot of i pa /i pc vs. ffiffiffi m p and the higher values of i pa /i pc for most of the complexes suggest adsorption of the product [56] of reduction [Cu(L) 2 ] + on the glassy carbon electrode.…”