Valence state of manganese ions in the La$_{1-\alpha}$Bi$_\beta$Mn$_{1+\delta}$O$_{3\pm\gamma}$ ceramics

The valence state of the Mn ions in ceramic samples of the La$_{1-\alpha}$Bi$_\beta$Mn$_{1+\delta}$O$_{3\pm\gamma}$ composition (LBMO) has been studied using the X-ray photoelectron spectroscopy. The presence of Mn$^{3+}$ and Mn$^{4+}$ ions in these compounds has been shown. The relative content Mn$^{3+}$/Mn$^{4+}$ has been determined by means of fitting the experimental Mn 2$p$ spectra by the superposition of theoretical spectra of Mn$^{3+}$ and Mn$^{4+}$ ions. The elemental composition of the samples has been determined by the X-ray photoelectron spectroscopy and electron probe microanalysis. It has been established that the relative content of Mn$^{4+}$ ions correlates with parameter $\delta$, which characterizes the deviation of the actual elemental composition of the La$_{1-\alpha}$Bi$_\beta$Mn$_{1+\delta}$O$_{3\pm\gamma}$ ceramics from stoichiometry La$_{1-x}$Bi$_x$MnO$_3$.