Measurements were made of the diffusion of radioactive 133Xe in single crystals. Two techniques were used to introduce the Xe. One was an homogeneous doping method in which Xe was introduced via the decay of homogeneously distributed 133I. The other was a recoil doping technique in which Xe was recoiled into the specimen from an external fissionable source. It was found that the results for both techniques were consistent with a classical diffusion model and with each other. At 150 to 400C, the diffusion could be described by:

D (cm2/s) = 0.57 exp[-1.01(eV)/kT]

Rare Gas Diffusion in Cesium Iodide: Use of Fission Recoil Doping Techniques. T.S.Elleman, L.D.Mears, H.P.Christman: Journal of the American Ceramic Society, 1968, 51[10], 560-4