Experimental Investigation of the EPR Parameters and Molecular Orbital Bonding Coefficients for VO2+ Ion in NaH2PO4·2H2O Single Crystals

Abstract

Electron paramagnetic resonance (EPR) spectra of VO2+ ions in NaH<inf>2</inf>PO<inf>4</inf>·2H<inf>2</inf>O single crystal have been studied. The spin-Hamiltonian parameters and molecular orbital bonding coefficients were calculated. The angular variation of the EPR spectra shows two different VO2+ complexes. These are located in different chemical environment and each environment contains four magnetically inequivalent VO2+ sites. The crystal field around VO2+ ion is approximately axially symmetric since a strong V=O bond distorts the crystal lattice. Spin Hamiltonian parameters and molecular orbital bonding coefficients were calculated from the EPR data and the nature of bonding in the complex was discussed together. © 2016 Elsevier B.V.