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Updated: Apr 28, 2026
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Local structure and La L1 and L3-edge XANES spectra of lanthanum complex oxides
Hiroyuki Asakura1, Tetsuya Shishido, Kentaro Teramura
1Synchrotron Radiation Research Center, Nagoya University , Furo-cho, Chikusa, Nagoya 464-8603, Japan.
Abstract:
La L1 and L3-edge X-ray absorption near-edge structure (XANES) of various La oxides were classified according to the local configuration of La. We found a correlation between both of the areas of the pre-edge peaks of the La L1-edge XANES spectra and the full width at half-maximum of white line of La L3-edge XANES spectra and the local configuration of La. Theoretical calculation of the XANES spectra and local density of states reveals the difference of La L1 and L3-edge XANES spectra of various La compounds is related to the p-d hybridization of the unoccupied band and broadening of the d band of La induced by the difference of local configuration. In addition, simplified bond angle analysis parameters defined by the angles of the La atom and the two adjacent oxygen atoms are correlated to the pre-edge peak intensity of the La L1-edge XANES spectra. These results indicate that quantitative analysis of La L1 and L3-edge XANES spectra could be an indicator of the local structure of La materials.
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