[5] Correlation between Kolmogorov-Sinai entropy and self-diffusion coefficient in simple fluids

The relationship between the Kolmogorov-Sinai entropy, h_KS and the self-diffusion coefficient D is studied for two classical simple fluid systems with purely repulsive potentials (one system with a Wayne-Chandler-Anderson potential and the other with a hard-sphere potential). Numerical simulation data for h_KS and D, normalized by the average collision frequency ν and the diameter of the particle σ as natural units of time and distance, reveal that, in the region spanning from normal liquid up to near solidification (0.50<~ρ<~0.93), the Kolmogorov-Sinai entropy has a power law dependency on the self-diffusion coefficient of the form h_KS/ν∝(D/σ²ν)^η, in which η is independent of density and temperature.