EPR studies of VO2+ doped bis(saccharinato)bis(pyridine) zinc (II) single crystals

Abstract

Electron paramagnetic resonance (EPR) studies of vanadyl ions, VO2+. as paramagnetic impurity in bis(saccharinato)bis(pyridine)zinc (II) [hereafter, Zn(sac)(2)(py)(2)] are made at room temperature. The angular variation of the EPR spectra has shown that three different VO2+ complexes are located in different chemical environments and each environment contains two magnetically inequivalent VO2+ sites in distinct orientations occupying substitutional positions in the lattice and show very high angular dependence. The spin-Hamiltonian parameters are determined and these parameters have been used to assess the bonding coefficients of the VO2+ ion in [Zn(sac)(2)(py)(2)] lattice. The values of spin-Hamiltonian parameters indicate that the VO2+ ions in [Zn(sac)(2)(py)(2)] were present in octahedral coordination with a tetragonal compression and belong to C-4v symmetry. The parallel and perpendicular components of axially symmetric g and hyperfine tensors are evaluated and the results are discussed. (C) 2009 Elsevier B.V. All rights reserved.