The local structure and dynamics of molten LiF-KF mixtures were studied using nuclear magnetic resonance and molecular dynamics simulations. The self-diffusion coefficients at 1123K, over the full composition range around the liquidus temperature, were measured and calculated. Close to the liquidus temperature, DF, DLi and DK changed with composition in a manner that mimicked the phase-diagram shape. At 1123K, DF, DLi and DK depended linearly upon the LiF molar fraction. The results showed that the composition affected the self-diffusion of anions and cations more weakly than did the temperature. The activation energy for diffusion could be correlated with the strength of anion-cation interaction in molten fluoride salts.

Diffusion Coefficients and Local Structure in Basic Molten Fluorides: in situ NMR Measurements and Molecular Dynamics Simulations. Sarou-Kanian, V., Rollet, A.L., Salanne, M., Simon, C., Bessada, C., Madden, P.A.: Physical Chemistry Chemical Physics, 2009, 11[48], 11501-6