An investigation was made of the self-diffusion of 131I in monocrystalline and polycrystalline material; using both the sectioning and Gruzin methods. The combined results for single crystals, at 405 to 560C, could be described by:

D (cm2/s) = 0.39 exp[-29.15(kcal/mol)/RT]

while those at 155 to 280C could be described by:

D (cm2/s) = 2.6 x 10-5 exp[-16.5(kcal/mol)/RT]

The combined results for polycrystals at 405 to 560C could be described by:

D (cm2/s) = 0.85 exp[-30.20(kcal/mol)/RT]

while those at 155 to 338.5C could be described by:

D (cm2/s) = 2 x 10-5 exp[-16.15(kcal/mol)/RT]

The polycrystals which were used were prepared via the deformation and recrystallization of monocrystals.

S.M.Klotsman, I.P.Polikarpova, A.N.Timofeev, I.S.Trakhtenberg: Fizika Tverdogo Tela, 1967, 9[9], 2487-502