X-ray absorption study of molten uranium chloride system

Okamoto, Yoshihiro  ; Akabori, Mitsuo; Ito, Akinori; Ogawa, Toru

We report local structural features of molten UCl with LiCl-KCl eutectic probed by the U L-edge XAFS(X-ray absorption fine structure). The XAFS measurements were performed in a transmission mode at the BL27B station of the Photon Factory(High Energy Accelerator Organization, Tsukuba, JAPAN). Sample prepared by chlorination of uranium hydride and then reduction with zinc powder was sealed in a quartz cell under reduced pressure. The nearest U-Cl distance and the coordination number of Cl around U ion were obtained by a curve fitting of the 1st shell XAFS function k(k). The pair potential in the U-Cl correlation was evaluated from XAFS simulation by combinational use of the MD and the FEFF8. In addition, valence state of uranium in the melt was evaluated by XANES(X-ray absorption near edge structure) spectra.