Self-diffusion in single crystals was measured at 496 to 640K using 127mTe and a sputtering technique for serial sectioning. Diffusion parallel to the c-axis was described by:

D(m2/s) = 6 x 10-5 exp[-1.53(eV)/kT]

and that perpendicular to the c-axis by:

D(m2/s) = 2 x 10-3 exp[-1.72(eV)/kT]

M.Werner, H.Mehrer, H.Siethoff: Journal of Physics C, 1983, 16[32], 6185-95