Structural characterization of La1-xMnO3±δ by x-ray diffraction and x-ray absorption spectroscopy -: art. no. 014412

Structural and magnetic properties of nanocrystalline compounds of the general formula La1-xMnO3+delta have been investigated combining x-ray diffraction and x-ray absorption spectroscopy in order to achieve an accurate description of the sample atomic structure in relation with its magnetic properties. The study reveals the segregation of different phases instead of a homogeneous sample composition. Interesting is the segregation of a vacancy-doped phase LayMnO3 whose composition is the same (ysimilar to0.9) for all the investigated samples, independently of the average sample composition. Since this phase is found to be principally responsible for the magnetic properties of these compounds, such a phase separation explains the largely composition-independent magnetic properties observed in the range 0.9greater than or equal toLa/Mngreater than or equal to0.7.