Chemical self-diffusion coefficients, D, as a function of temperature and metal vapor pressure, PCd, were studied in undoped single crystals at high temperatures. The value of D was about 3 orders of magnitude faster than that for self-diffusion under the same conditions. It was shown that doubly-ionized interstitial metal atoms were the predominant diffusible defects at high metal vapor pressures. The value of D was found to be almost independent of the metal vapor pressure for undoped CdSe at high PCd. At 565 to 700C, D could be described by:

D (cm2/s) = 1.6 x 10-2 exp[-0.41(eV)/kT]

Chemical Self-Diffusion in Undoped ZnS and in Undoped CdSe. K.Lott, T.Nirk, O.Volobujeva: Crystal Engineering, 2002, 5[3-4], 147-53