Experimental verification of the Stokes-Einstein relation in liquid Fe-FeSat 5 GPa

Experiments have been performed at 5 GPa on liquid Fe-FeS in order to deter mine Fe and S self-diffusivity as a function of temperature. The viscosity of the sample was then obtained using the Stokes-Einstein relation. The res ults are in excellent agreement with previous experiments where the viscosi ty of a material of the same composition under similar conditions was measu red directly. These results support high, near-metallic, values of diffusiv ity and low viscosity in liquid Fe-S up to a few hundred K above the eutect ic temperature, in contrast with some previous studies. Moreover, these res ults fully confirm the validity of the Stokes-Einstein relation between vis cosity and diffusion coefficients for Fe0.61S0.39.