Entropy and transport properties of liquid metals along the melting curve

Abstract

Molecular dynamics simulations are performed for several monatomic metals and Fe0.9Ni0.1 metallic alloy to study the transport properties and entropy of liquids along melting curve. Our results show that the self-diffusion coefficients and viscosity of liquids increase with increasing pressure along the melting curves. Analysis suggests that, at high pressure conditions, the pair correlation entropy S2 of liquids along melting curve is bout −3.71kB, independent of the pressure and variety of liquids, which indicates that there is no obvious change in liquid structure along the melting curve. The Rosenfeld entropy-scaling laws with S2 = −3.71kB and the special values of scaling parameters can give reasonable estimates for the self-diffusion coefficients and viscosity of liquid metals along melting curves. The effect of pressure on transport coefficients can be quantified through its corresponding effect on the melting temperature and number density, and this result is in consistent with the Andrade’s model. In addition, the variation of S2 provides a useful, experimentally accessible, structure-based criterion for freezing of liquid metals.