Electron spin resonance as probe to characterize the spin and charge order in La2NiO4.12
Résumé
We used electron spin resonance (ESR) and magnetic susceptibility to study the magnetic correlations in polycrystalline La2NiO4.12 prepared by modified sol–gel method. We observed an evolution of the ESR signal with temperature, from 4 K to 300 K, with marked changes at 220 K and 150 K. Such changes are related to the particular order of holes and spins previously observed in this system by neutron diffraction by other authors. Magnetic susceptibility measurements confirm the charge and spin order temperatures in this composition.