Quasi-elastic neutron scattering was used to measure the absolute value of self-diffusion in the liquid. Compared to other mono-atomic liquids, such as Ni or Ti, the self-diffusivity was found to be an order of magnitude faster near to the melting point, and exhibited non-Arrhenius behaviour. Above 1325K, the activation energy for self-diffusion was low and obeyed the Stokes-Einstein relationship. Even though the packing density of liquid germanium was less than that of simple metallic melts (Pb, Sn), the temperature dependence of the self-diffusivity did not obey the D ∝ Tn(n ≃ 2) law which was observed for uncorrelated binary collisions of hard spheres.

Influence of Structural Changes on Diffusion in Liquid Germanium. S.M.Chathoth, B.Damaschke, T.Unruh, K.Samwer: Applied Physics Letters, 2009, 94[22], 221906