ESR studies on copper(II) complexes of 1,3-diaminopropane and 1,2-diaminopropane

The synthesis and characterization of (NH2RNH2)(3)CuCl2.H2O complexes, wher e R = (-CH2-)(3) or (-CH(CH3)-CH2-) ore reported. The complexes are octahed ral. The ESR spectra of polycrystalline samples showed broad lines, which i ndicate spin-exchange interactions between copper(II) ions. In solution at 77 K, the spectra show axial type symmetry with d(x2-y2) ground state of a tetragonal distortion around copper(II) ion. The bonding parameters alpha(2 )(2) and beta(1)(2) indicate a covalent character of in-plane sigma and pi bondings, while beta(2) indicates ionic out-of-plane pi bondings. d-Orbital populations of the complexes indicate, that the unpaired electron site is mainly in d(x2-y2) orbital.