Abstract:
X-ray absorption spectroscopy has been applied for a characterization of charge states of cobalt ions of nanostructured GdBaCo$_{2}$O$_{5.5}$ complex oxides. The analysis of experimental and theoretical data has allowed establishing a reduction in the oxidation degree from Co$^{3+}$ to Co$^{2+}$ for a part of cobalt ions in GdBaCo$_{2}$O$_{5.5}$ nanoceramics obtained by torsion under pressure.