Reaction of Curium(III) Ions with Oxo-Species in Alkali Chloride Melts

Abstract

Electronic absorption spectra of curium(III) chloro-species were measured in 3LiCl-2KCl (at 450 oC) and NaCl-2CsCl (at 550, 650 and 750 oC) eutectic melts and the molar absorption coefficients determined. The effect of oxide species addition to the melt on the absorption spectra of curium was studied. A new species, evident from the absorption bands around 360 nm, is formed when barium oxide is dissolved in the melt or O2-Cl2 or Ar-HCl-H2O gas mixtures bubbled through. This species is ascribed to soluble curium oxychloride. It does not react with chlorine bubbled through the melt unless there is carbon present.