A simple theoretical model was developed, for the thermal diffusivity of Cr2+ ions in bulk ZnSe single crystals and polycrystalline samples, on the basis of optical absorption measurements in the 1200 to 2800nm spectral region. Sputtered metallic Cr and powders were used as dopant sources. Diffusion appeared to be faster in polycrystalline samples

than in single crystals, for annealing temperatures below 910C. The activation energy, which was lower in polycrystals, depended upon the nature of the dopant source (table 3, figure 7).

Thermal Diffusion of Cr2+ in Bulk ZnSe. J.O.Ndap, K.Chattopadhyay, O.O.Adetunji, D.E.Zelmon, A.Burger: Journal of Crystal Growth, 2002, 240[1-2], 176-84

 Table 3

 Thermal Diffusivity Parameters for Cr2+ in ZnSe