An electrolytic technique, involving a double cell system, was used to measure the H diffusivity at 273 to 350K. The Arrhenius plots were linear:

D (cm2/s) = 2.91 x 10-3 exp[-5.3(kcal/mol)/RT]

M.Yoshihara, R.B.McLellan: Acta Metallurgica et Materialia, 1990, 38[6], 1007-12