An investigation was made of the self-diffusion of 134Cs in monocrystalline and polycrystalline material; using both the sectioning and Gruzin methods. The data (tables 248 and 249) indicated that intercrystalline diffusion within the temperature range studied did not contribute significantly to the diffusion process. The overall results for monocrystalline and polycrystalline material at 294 to 500C could be described by:

D (cm2/s) = 85 exp[-37.94(kcal/mol)/RT]

according to the sectioning method, and by:

D (cm2/s) = 75 exp[-37.79(kcal/mol)/RT]

according to the Gruzin method. The combined results for single crystals could be described by:

D (cm2/s) = 80 exp[-37.86(kcal/mol)/RT]

while the combined results for polycrystals could be described by:

D (cm2/s) = 42 exp[-36.89(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

Table 248

Self-Diffusion of 134Cs in Single Crystals of CsI

Table 249

Self-Diffusion of 134Cs in Polycrystalline CsI