The Eu diffusion in was studied at 780 to 1100C. Data on the diffusion coefficient and activation energies for the Eu diffusion in monocrystalline and polycrystalline SmS samples were obtained. In the former, Eu was shown to migrate predominantly over lattice sites (D = 10−12 to 10−9cm2/s). In polycrystals, diffusion was found to exhibit a complex pattern and had both a slow (D = 10−10 to 10−9cm2/s) and a fast (D = 10−8 to 10−7cm2/s) component. The Eu diffusion in a polycrystal was due mainly to Eu migration over the boundaries of single-crystal grains in the polycrystal, whose characteristic size was assumed to be that of X-ray coherent-scattering regions.

Europium Diffusion in SmS. A.V.Golubkov, V.A.Didik, V.V.Kaminskii, E.A.Skoryatina, V.P.Usacheva, N.V.Sharenkova: Physics of the Solid State, 2005, 47[7], 1233-5