Theoretical Studies of Electronic Paramagnetic Resonance g Factors for La2Mg3(NO3)12⋅24H2O

Abstract

Lanthanum magnesium double nitrate (LMN) crystals can be used as material for adiabatic demagnetization, magnetic thermometers and a proton spin-polarized target in both physics and polarized neutron diffraction. In the past years, the double nitrates doped with transition metal or rare earth ions have been studied by experimental and theoretical methods. For instance, the electronic paramagnetic resonance (EPR) g factors of the Ce3+ ions in La2Mg3(NO3)12⋅24H2O crystal were measured decades ago. But until now, these useful experimental results have not been theoretically explained. In this work, The EPR g factors of the trigonal Ce3+ centers in La2Mg3(NO3)12⋅24H2O are theoretically studied from the perturbation formulae of the EPR parameters for a 4f1 ion under the trigonal symmetry crystal field. The used crystal parameters are obtained from the superposition model and the local structure of the studied crystal. The calculated results are reasonably constant to the observed values. The results are discussed.