Electron paramagnetic resonance studies on Cu(II) ions doped in Tl2Ni(SO4)2·6H2O single crystals

Abstract The X -band electron paramagnetic resonance (EPR) studies on a single crystal of Cu(II) ions doped in thallium nickel sulphate hexahydrate have been made over an extended temperature range of 120 K to 390 K. Two chemically equivalent, but magnetically inequivalent Cu(II) complexes have been observed. The angular variation spectra reveal that the Cu(II) ion enters the Ni(II) site in the host lattice. From the observed EPR spectrum the spin-Hamiltonian parameters have been evaluated. The orbital reduction factor and covalency parameters are also evaluated. The optical absorption spectrum exhibits a broad band at 11,850 cm −1 which is assigned to the transition 2 B 1 g → 2 B 2 g .