The penetration depth of Br2 into the crystals was measured at 375 to 600C by using the OH- center as an indicator. A plot of the inverse square of the penetration depth versus the inverse partial pressure of Br led to a linear relationship; thus indicating that the Br diffused in the form of molecules. The intercept and slope of the plot showed that the diffusivity could be described by:

D (cm2/s) = 0.17 exp[-0.95(eV)/kT]

Diffusion of Br2 Molecules in KBr. T.Ikeda: Journal of the Physical Society of Japan, 1976, 41[6], 1968-73