Local and electronic structure of AmO and AmO with XAFS spectroscopy

Nishi, Tsuyoshi; Nakada, Masami  ; Suzuki, Chikashi ; Shibata, Hiroki ; Ito, Akinori; Akabori, Mitsuo; Hirata, Masaru 

XAFS studies were performed in a study of americium sesquioxide (AmO) with A-type rare earth oxide structure and americium dioxide (AmO) with fluorite structure. EXAFS results for Am-L absorption edge of AmO and AmO were good agreement with the crystallographic data from X-ray diffraction analysis. In order to characterize XANES in aspect of the electronic states, the theoretical assignments for the AmO and AmO were performed with the all-electron full potential linearized augmented plane wave (FP-LAPW) method. The theoretical XANES spectra of AmO and AmO well reproduced the experimental ones. In addition, it was found that the white line peak was created due to the interaction between Am-d and O-p components, and the broad peak and the tail peak were created due to the interaction between Am-d and O-d component.