Structures of chloro-uranium species in molten LiCl-BeCl2 eutectic: A combined X-ray and electronic absorption spectroscopy study

The structures and interatomic distances of various chloro complexes of uranium in LiCl-BeCl2 eutectic melt at 380 °C have been determined from EXAFS measurements. Dissolution of UCl4 and UO2Cl2 (in the absence of a chlorine atmosphere) generated UCl62- ions. Similarly, dissolution of UCl3 generated UCl63- complexes but dissolution of UO2Cl2 under a chlorine atmosphere yielded a mixture of UCl62- and UO2Cl42-, deduced from electronic absorption spectra measurements. Interatomic distances and uranium coordination are compared with earlier data in molten LiCl, both in melts and for quenched samples at room temperature.