Electronic structures of La0.7Ca0.3MnO3 and La0.7Ce0.3MnO3 by X-ray absorption spectroscopy

Electronic structures of hole-doped and electron hole-doped manganites, La0.7Ca0.3MnO3 and La0.7Ce0.3MnO3, have been elucidated by X-ray absorption near-edge structure (XANES) spectra of O K- and Mn L-3,L-2-edges. In the electron-doped system, La0.7Ce0.3MnO3, the spectral features of 0 K-edge spectra are shifted by similar to1 eV towards the higher energy side and reduction of Mn valency from 4(+) and 3(+) to 3(+) and 2(+) is expected when compared to hole-doped manganite. The XANES of Ce M-5,M-4-edges indicates a tetravalent state for Ce, similar to that in CeO2. Ce4+ is incorporated into the lattice of LaMnO3, resulting in the modification of MnO6 octahedra and also indicating strong hybridization of Ce 5d and/or Ce 4f states with O 2p states.