INVESTIGATIONS OF THE EPR PARAMETERS FOR Cu2+ IN [Cu(ipt)(dap)H2O]nxnH2O
Y.-K. Cheng, S.-Y. Wu, C.-C. Ding, G.-L. Li, M.-Q. Kuang
University of Electronic Science and Technology of China, Chengdu 610054, P. R. China
Keywords: electron paramagnetic resonance (EPR), Cu
Abstract
The electron paramagnetic resonance (EPR) parameters (g factors and hyperfine structure constants) for Cu2+ in [Cu(ipt)(dap)H2O] n × n H2O (ipt is isophthalic acid, dap - 1,3-diaminopropane) are theoretically investigated from the high order perturbation formulas of these parameters for a 3 d 9 ion in a rhombically elongated octahedron. The ligand orbital and spin-orbit coupling contributions are included from the cluster approach because of strong covalency of the system. The nearly axial anisotropies of the g factors and hyperfine structure constants are correlated to the significant elongation distortion of the five-fold coordinated Cu2+ (in a distorted square pyramidal [CuN2O3] group). Nevertheless, the perpendicular anisotropies arising from the nonequivalent planar ligands are largely concealed by the experimental uncertainties. The theoretical analysis of the EPR behaviours for [Cu(ipt)(dap)H2O] n × n H2O would be helpful to understand the local structures and properties of this and relevant systems.
|
