A serial-sectioning investigation was made of the effect of hydrostatic pressures upon the diffusion of 36Cl in single crystals (table 60). The data for pressures of 1 to 16.5kbar, at a temperature of 745C, indicated an activation volume of 11.8cm3/mol. Those for pressures of 1 to 17kbar, at a temperature of 685C, indicated an activation volume of 11.7cm3/mol, and those for pressures of 10.8 to 17kbar, at a temperature of 797C, indicated an activation volume of about 14cm3/mol. Diffusion and Electrical Conductivity of Alkali Halides. H.W.Schamp: US Atomic Energy Report TID-23874, 1967