Structure and dynamics of liquid iron under Earth's core conditions

First-principles molecular-dynamics simulations based on density-functional theory and the projector augmented wave (PAW) technique have been used to study the structural and dynamical properties of liquid iron under Earth's core conditions. As evidence for the accuracy of the techniques, we present PAW results for a range of solid-state properties of low- and high-pressur e iron, and compare them with experimental values and the results of other first-principles calculations. In the liquid-state simulations, we address particular effort to the study of finite-size effects, Brillouin-zone sampl ing, and other sources of technical error. Results for the radial distribut ion function, the diffusion coefficient, and the shear viscosity are presen ted for a wide range of thermodynamic states relevant to the Earth's core. Throughout this range, liquid iron is a close-packed simple liquid with a d iffusion coefficient and viscosity similar to those of typical simple liqui ds under ambient conditions.