Ushio Sakaguchi

Angular variation of the orthorhombic ESR spectra of Cu(II)

Abstract Equations are developed, based on second-order perturbation theory, for the resonance frequencies and intensities of ESR transitions of an orthorhombic system such as Cu(II). The results obtained assist in the initial estimate of values for the quadrupole coupling constant when a computer diagonalization of the complete matrix is to be performed.

Electron spin resonance study of zinc-doped single crystals of copper propionate monohydrate

Abstract Electron spin resonance spectra have been obtained at liquid nitrogen temperature for zinc-doped copper propionate monohydrate single crystals and analyzed. The principal values of the g and A tensors and the direction cosines of the principal axes have been determined for four sites of the copper-zinc pairs ( S = 1 2 ). The g and A values are consistent with the results of Kokoszka and co-workers ( 20 ) obtained from the powder spectra. The small rhombic character in g value has been noted and compared with the data on zinc-doped copper acetate monohydrate. The results suggest that the exchange interaction comes mainly from superexchange via the bridging carboxyl groups.

Proton magnetic resonance study of the complexes dichlorobis(picoline)cobalt(II) in solution

Abstract Paramagnetic shifts have been measured for the ligand protons of the tetracoordinated complexes dichlorobis(picoline)cobalt(II) dissolved in deuteriochloroform, and used to evaluate proton-electron hyperfine coupling constants. Electron spin relaxation times are estimated using line width data for the ligand and the solvent protons.

The singlet-triplet separation in dichloromonoaquopyridine-N-oxide copper (II) as determined by the proton spin-lattice relaxation

Abstract The singlet-triplet separation has been determined at 913 ± 150 cm −1 for dichloromonoaquopyridine- N -oxide copper (II) by measuring the proton spin-lattice relaxation time and the ESR intensity as a function of temperature. This method for the determination of the singlet-triplet separation from the proton T 1 may be applied to many exchange-coupled dimeric copper complexes.

Stereoselective association between acetylacetonatobis(ethylenediamine)cobalt(III) cation and malonate anion as studied by the rate of amine hydrogen exchange

The rate of amine hydrogen exchange for acetylacetonatobis(ethylenediamine)cobalt(III){[Co(acac)en)2]2+} in the presence of malonate ion indicates that the malonate ion associates with the complex from the side opposite to acac and hydrogen bonds only to trans hydrogens in the direction approximately parallel to the two-fold axis of the complex.