The 133Xe was injected into single crystals via fission recoil, and the gas release kinetics were studied during subsequent annealing at 750 to 1000C. The release kinetics were found to be diffusion-controlled, and the data could be described by:

D (cm2/s) = 9.50 x 106 exp[-4.42(eV)/kT]

Trapping of the Xe by radiation-induced defects was observed at higher gas concentrations, and the trap concentrations were found to be dose- and temperature-dependent. The traps appeared to be radiation-generated defect clusters. The results were most consistent with a diffusion model that was based upon the transport of gas atoms in mobile defect clusters.

Diffusion and Trapping of Rare Gas Xenon in Calcium Fluoride Single Crystals. A.S.Ong, T.S.Elleman: Journal of Nuclear Materials, 1972, 42[2], 191-202

 

Table 162

Arrhenius Parameters for Interdiffusion

in the CaF2-SrF2 System at 1100 to 1320C

 

CaF2 (mol%)

Do (cm2/s)

Q (kcal/mol)

0

1.91 x 103

89.6

10

1.45 x 103

88.4

20

1.39 x 103

87.6

30

3.26 x 103

89.7

40

1.77 x 104

94.4

50

6.37 x 104

97.8

60

1.81 x 105

100.6

70

3.65 x 105

102.4

80

2.70 x 105

101.5

90

1.23 x 105

99.0

100

2.88 x 105

102.1