EXAFS and XANES studies of americium dioxide with fluorite structure

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

EXAFS and XANES analysis were applied in a study of americium dioxide (AmO) with fluorite structure. EXAFS result for Am-L absorption edge of AmO was good agreement with the long-ranged structural data from X-ray diffraction analysis. In order to characterize XANES in aspect of the electronic structure, the theoretical assignment for the AmO was performed with the relativistic DV-X molecular orbital method. The calculated XANES spectrum well reproduced the experimental spectrum. The theoretical assignment of the XANES spectra is very useful for the development of MA-MOX fuel for the future nuclear fuel cycle.