Relation between Self-Diffusion and Viscosity in Dense Liquids: New Experimental Results from Electrostatic Levitation

摘要

By using the technique of electrostatic levitation, the Ni self-diffusion, density, and viscosity of liquid Zr_(64)Ni_(36) have been measured in situ with high precision and accuracy. The inverse of the viscosity, 77, measured via the oscillating drop technique, and the self-diffusion coefficient D, obtained from quasielastic neutron scattering experiments, exhibit the same temperature dependence over 1.5 orders of magnitude and in a broad temperature range spanning more than 800 K. It was found that D_η = const for the entire temperature range, contradicting the Stokes-Einstein relation.