SELF-DIFFUSION IN LIQUID METALS

抄録

The relaxation model previously proposed by the authors was applied to the self-diffusion process in liquid metals. A Lennard-Jones type pair potential function was used to evaluate the term related to the frequency of the oscillatory motion in liquids. The self-diffusivity of liquid metals can be calculated simply from the melting temperature, T_m, and the liquid density, ρ, with the use of the final formulae:
D=0.135_z(kT)^1/2m^-1/6ρ₀^-1/3(T/T_m)^1/2(1-ρ/ρ₀)=0.555(kT)^1/2m^-1/6/ρ_m^-1/3(T/T_m)^1/2(1-ρ/1.068ρ_m)
The agreement of calculated values with observed ones is satisfactory, especially for temperature dependency. The physical meaning of the model parameters, z and ρ_o is also discussed.