Abstract
Behaviours of the evaporation of Ba from BaB6 has been studied. A semiempirical relation was given by log P (Torr) = 3.0 (±0.1) -15, 300±1, 000/T
in the temperature range of 1270 °K< T< 1670 °K. The evaporation of Ba was found to be emphasized when there existed an impurity layer on the surface. The thickness of the layer was estimated to be less than 100Å and was composed of Ba and O atoms.
