The capillary reservoir technique was used to study the diffusion of 18F in molten mixtures (table 179). It was suggested that AlF63-, AlF4-, NaF and Na2F+ complexes were present in the melt. The activation energy for 18F diffusion in samples with 13.5mol%AlF3, at 938 to 1070C, was 12.5kcal/mol. The activation energy for diffusion in samples with 37.5mol%AlF3, at 928 to 999.7C, was 7.0kcal/mol.

Na-22 and F-18 Diffusion in Na and Al Fluoride Baths. D.Harari, F.Lantelme, M.Chemla: Journal de Chimie Physique et de Physicochimie Biologique, 1969, 66[7-8], 1286-91