Transport coefficients of liquids from first principles

The use of first-principles molecular dynamics to calculate the viscosity of liquid metals using the Green–Kubo relations is described. The first-principles techniques are based on density functional theory, the pseudopotential approximation, and plane-wave basis sets. The statistical-mechanical basis of the Green–Kubo relations is summarised, and extensive first-principles molecular dynamics simulations of liquid aluminium are presented to demonstrate that the method works in practice. Calculated viscosity results are reported for two important systems: liquid iron at Earth's core conditions, and liquid selenium at states on the liquid–vapour curve. The significance of the viscosity results for an understanding of these systems is discussed.