Samarium diffusion in polycrystalline samarium sulfide

Abstract

The diffusion of samarium in polycrystalline samarium sulfide with a superstoichiometric composition of Sm1.13S has been studied at T = 1000 and 1100°C. It is concluded that Sm atoms predominantly migrate over the boundaries of monocrystalline domains of the polycrystalline sample. The diffusion coefficient varies within D ≈ 10−2−10−3 cm2/s. In the temperature dependence of the diffusion coefficient, the diffusion activation energy is evaluated at E ∼ 4.6 eV and the preexponential term at D0 ≈ 1.8 × 1015 cm2/s.