Electron Paramagnetic Resonance of Mn2+ in Ni(CH3COO)2·4H2O and NiSO4·7H2O Single Crystals

Electron paramagnetic resonance of Mn2+ has been studied in nickel acetate tetrahydrate [Ni(CH3COO)2·4H2O] and nickel sulfate heptahydrate (NiSO4·7H2O) at 300°K. The Mn2+ was found to substitute for Ni2+ in both the systems and exhibit inequivalent magnetic complexes, two for the bimolecular Ni(CH3COO)2·4H2O and four for the tetramolecular NiSO4·7H2O. Besides, the Mn2+ resonance lines exhibited a direct dependence of linewidth on the intensity of Zeeman field and a shift in g value towards the lower side from the free-spin g value. These features have been explained in terms of the interaction of the Mn2+ ion with Ni2+ host ions.