The diffusivity of Pt was studied at 0 to 725C by using Rutherford back-scattering spectrometry. The diffusion coefficients were deduced from the measured diffusion profiles. It was found that the diffusion results obeyed:

D (cm2/s) = 2.6 x 10-9 exp[-18.6(kcal/mol)/RT]

Diffusion along the grain boundaries was between 2 and 3 times as fast as bulk diffusion.

T.G.M.Van den Belt, J.H.W.De Wit: Thin Solid Films, 1983, 109[1], 1-10