Structural effects in the EPR spectra of Ni in La2Ni0.5Li0.5O4
نویسندگان
چکیده
Electron paramagnetic resonance ~EPR!, Raman scattering, and neutronand x-ray-diffraction experiments were performed in polycrystalline samples of La2Ni0.5Li0.5O4 as a function of temperature. Structural studies confirm a partial cation ordering of Ni and Li at the metal sites. As the temperature decreases, EPR measurements show an increasing g-value anisotropy (g'2g i) and neutron and x-ray-diffraction experiments an increase of the c/a ratio. These results are interpreted in terms of the stabilization of the Ni(3d) A1g low-spin configuration in the NiO6 Jahn-Teller distorted octahedra.
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