NEXAFS studies of La(0.8B)i(0.2)Fe(1-x)Mn(x)O(3)(0.0 <= x <= 0.4) multiferroic system using x-ray absorption spectroscopy

Abstract

We report the electronic structure studies of well-characterized La0.8Bi0.2Fe1-xMnxO3 (LBFM, 0.0 <= x <= 0.4) multiferroic samples investigated by soft x-ray absorption spectroscopy at O K-, Mn L-3,L-2-, Mn K-, Fe L-3,L-2- and La M-4,M-5-edges along with the spectra of reference compounds. The investigations are performed to find out the chemical states and crystal field symmetry of ions present in the LBFM multiferroic samples after the substitution of Mn ions at Fe sites. Studies reveal a slight shift in the peak positions of O K-edge spectra along with growth in intensities of low-energy features. An analysis of the Mn L-3,L-2- and K-edge, in addition to the comparison with the spectra of reference compounds, indicates that the Mn ions are present in mixed valence states. It is found that the Mn ions are mainly in +3 states along with a small contribution of +2 and +4 ones. The study of Fe L-3,L-2-edge confirms the trivalent state of Fe ion. M4,5-edges of La corroborate the +3 state of La in the system. Atomic multiplet calculations are also performed on Fe L-3,L-2-, Mn L-3,L-2- and La M-4,M-5-edges to further verify the valency, symmetry and the crystal field splitting.