The isotope effect for diffusion through single-crystal membranes (6.3 x 10-3cm-thick) was investigated by using the permeation time-lag technique. It was found that the H/D diffusivity ratio (table 91) decreased markedly as the temperature was decreased to below 460K. The H diffusivity at 367.2K was equal to 1.19 x 10-8cm2/s.
Y.Ebisuzaki, M.O’Keeffe: Journal of Chemical Physics, 1968, 48[4], 1867-8
Table 92
Parameters for H Isotope Diffusion in Ni Single Crystals at 670 to 1270K
Isotope | Do (cm2/s) | E (kcal/mol) |
H | 7.04 x 10-3 | 9.434 |
D | 5.27 x 10-3 | 9.243 |
T | 4.32 x 10-3 | 9.102 |