EPR and optical absorption studies of Cu 2+ doped l-arginine phosphate monohydrate single crystals — part II

Abstract

The EPR spectra of Cu 2+ ion in l-Arginine phosphate monohydrate (LAP) at X-band frequencies at room temperature reveal the presence of two magnetically inequivalent interstitial Cu 2+ sites in the lattice. The principal values of the g- and A-tensors indicate rhombic symmetry around the Cu 2+ ion. From the direction cosines of the principal values of the g- and A- tensors, the orientations of the sites in the lattice have been identified. The bonding parameters were evaluated and the ground state wave function of Cu 2+ ion was constructed. The ground state is found to be an admixture of ∣ x 2− y 2〉 and ∣3 z 2− r 2〉 orbitals. The optical absorption studies show four bands centered at 9803, 10 753, 15 748 and 16 666 cm −1 confirming the rhombic symmetry around the Cu 2+ ion. Using the observed bands the crystal field parameters have been evaluated.