A study was made of the release kinetics of radioactive Xe atoms from single crystals, following neutron irradiation. The results for undoped material, at 940 to 1320C, could be described by:

D (cm2/s) = 1 x 104 exp[6(eV)/kT]

The results for U-doped material, at temperatures ranging from 700 to 940C, could be described by:

D (cm2/s) = 1010 exp[6(eV)/kT]

Diffusion of Ar, Kr, and Xe in CaF2 Investigated on U-Doped Single Crystals of CaF2 after Neutron Irradiation. F.W.Felix, S.Y.T.Lagerwall: Physica Status Solidi A, 1971, 4[1], 73-9

Figure 32

Diffusion of 133Xe in CaF2