Mössbauer study of 57Fe-doped La0.5Sr0.5CoO3

Mossbauer and magnetization measurements have been performed on the La0.5Sr0.5Co0.97857Fe0.022O3 compound in the temperature range 100 K< T<293 K. It was shown that the most probable electronic state of the iron probe ions is a formal 4+ high-spin one. Such electronic Fe ion configuration is associated with the metallicity and confirms the delocalized eg electron character. The paramagnetic single-line component together with a broadened magnetic splitting was observed in the Mossbauer spectra well below the magnetic ordering temperature. This peculiarity is interpreted in terms of a La-rich inhomogeneity containing Co3+ ions mainly in the low-spin state as well as irregular La3+/Sr2+ ion distribution in the surroundings of the iron probe ions. The mechanism of the magnetic interactions is discussed.