NEUTRON-DIFFRACTION STUDY OF THE LI-CL DISTANCE IN MOLTEN MIXTURE SYSTEMS (LI,K)CL AND (LI,CS)CL

Neutron diffraction with a time-of-flight method has been performed for the molten binary systems (Li-7, K)Cl and (Li-7, Cs)Cl at 1073 K and 973 K, respectively, with the main aim of determining the change in the nearest neighbour Li-Cl distance with concentration; the concentrations investigated were x(LiCl) (mole fraction of LiCl) = 0, 0.20, 0.35, 0.50, 0.65 and 0.80 for the former, and 0, 0.10, 0.20, 0.35, 0.50, 0.65, 0.80 and 1 for the latter. It was found that the Li-Cl distance decreases with increasing concentration of KCl (or CsCl); this distance, as a function of molar volume in both systems, seems to lie on a single curve. The Li-Cl distance in the mixture (Li, Cs)Cl of x(LiCl) = 0.10 is shorter than that in pure LiCl by as much as 0.019 nm