The macroscopic diffusivities were measured, at temperatures of between 225 and 350K, by exploiting the Gorsky effect. The atomic ratio, H/(Pd + Pt), ranged from 0.03 to 0.29 (figure 33). Site-energy calculations showed that only I6, and some I5, sites were occupied and contributed to the diffusion. A comparison of Gorsky and Zener relaxation data revealed the existence of an unexplained upward deviation of the Arrhenius plot.

Diffusivity of H and D in Palladium-Platinum Alloys via Gorsky Relaxation. B.Coluzzi, C.Costa, A.Biscarini, F.M.Mazzolai: Journal of Physics - Condensed Matter, 1992, 4[22], 5155-66

Figure 33

Diffusivity of H in Pd85Pt15

(open squares: H/[Pd+Pt] = 0.29, filled squares: H/[Pd+Pt] = 0.03)