X-RAY SPECTRA AND CHARGE STATES OF CATIONS IN NANOSTRUCTURED MANGANITES La0.5Ca0.5MnO3 AND Nd0.5Sr0.5MnO3
V. V. Mesilov, V. R. Galakhov, S. N. Shamin, B. A. Gizhevskii, S. V. Naumov
Miheev Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, Ekaterinburg, Russia
Keywords: X-ray spectroscopy, nanostructured manganites, grinding in a vibration mill, calculations of atomic multiplets
Abstract
From the analysis of experimental X-ray absorption spectra and the calculation of atomic multiplets it is found that the grinding of powder manganites La0.5Ca0.5MnO3 and Nd0.5Sr0.5MnO3 in a vibration mill results in the formation of nanocrystallites and a partial transformation of trivalent manganese ions into tetravalent. It is shown that in nanostructured manganite La0.5Ca0.5MnO3 the energy gap between the occupied and unoccupied states is absent. It os found that Mn2+ ions arise in Nd0.5Sr0.5MnO3 due to more intense deformation during the grinding.
DOI: http://dx.doi.org/10.1134/S0022476615030166
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