Magnetic and electronic properties of RNiO3 (R = Pr, Nd, Eu, Ho and Y) perovskites studied by resonant soft x-ray magnetic powder diffraction

Soft x-ray resonant magnetic powder diffraction of the (1/2 0 1/2) reflection at the Ni L-2,L-3 edges is used to study the magnetic and electronic properties of a series of RNiO3 materials (with R = Pr, Nd, Eu, Ho and Y) below the metal-insulator transition. The polarization and energy dependence of the reflection gives further support for a non-collinear magnetic structure and charge disproportionation in the whole RNiO3 series. Only small changes in the spectra of the magnetic (1/2 0 1/2) reflection and in the absorption spectra could be detected. The results are discussed with comparison to charge transfer multiplet calculations. Our results emphasize that the lighter and heavier RNiO3 compounds are very similar from the point of view of their local electronic and magnetic state despite the strong change of the metal-to-insulator transition temperature.