Conditions Extrêmes et Matériaux : Haute Température et Irradiation
CEMHTI - UPR3079 CNRS

utilisateur non identifié  |   Login

View CEMHTI Publication

Return to publication search...
Ask for a reprint
email :


2010

ACL
doi
OpenAccess

M.Numakura, Y.Okamoto, T.Yaita, H.Shiwaku, H.Akatsuka, A.Nezu, K.Tajima, Y.Shimohara, C.Bessada, O.Pauvert, D.Zanghi, P.Chamelot, H.Matsuura, 'Local structural analyses on molten terbium fluoride in lithium fluoride and lithium–calcium fluoride mixtures', J. Fluorine Chem. 131 1039-1043 (2010) doi:10.1016/j.jfluchem.2010.07.011

X-ray absorption fine structure (XAFS) measurements on terbium fluoride in molten lithium fluoride and in molten lithium–calcium fluoride mixtures, (e.g. 0.20TbF3–0.80LiF, 0.20TbF3–0.62LiF–0.18CaF2, 0.20TbF3–0.48LiF–0.32CaF2, 0.50TbF3–0.50LiF, and 0.50TbF3–0.38LiF–0.12CaF2), have been carried out. In the solid state, coordination number of terbium (Ni) and inter ionic distances between terbium and fluorine in the first neighbor (ri) are nearly constant in all mixtures. In 0.20TbF3–0.80LiF, 0.20TbF3– 0.62LiF–0.18CaF2 and 0.50TbF3–0.50LiF mixtures, Ni’s decrease from ca. 8 to 6 and ri’s also decrease from ca. 2.29 to 2.26A˚ on melting. On the other hands, in molten 0.20TbF3–0.48LiF–0.32CaF2 and 0.50TbF3– 0.38LiF–0.12CaF2mixtures, Ni’s are slightly larger than 6 and ri’s do not change. These facts correspond to the amount of F supplied by solvent melts, i.e. the effect of CaF2 becomes predominant at bCaF2 > 0.32 in ternary 0.20TbF3–aLiF–bCaF2 mixtures and at bCaF2 > 0.12 in ternary 0.50TbF3–aLiF–bCaF2 mixtures.