X-ray absorption spectroscopy study of the La 0.7Ba 0.3Mn 1− xCo xO 3 system

Abstract

We report the transition-metal (Mn and Co) K-edge X-ray absorption spectroscopy (XAS) study of a series of La 0.7Ba 0.3Mn 1− x Co x O 3 ( 0⩽x⩽1) samples. Systematic chemical shifts to higher energy with the Co content ( x) are observed in both Mn and Co K-edge spectra. The chemical shift to higher energy in Mn K-edge spectra is caused by the decreased Mn 3+/Mn 4+ ratio due to Co substitution of Mn. The Co K-edge spectra show that the Co valence is between 2+ and 3+, which also increases with x. The effect of electronic structures on the physical properties are briefly discussed.