Bonding and disorder in liquid silicon

A first-principles molecular-dynamics study of metallic liquid silicon is presented. Our description of the local order is in excellent agreement with x-ray and neutron diffraction experiments. Analysis of the electronic charge density shows persistence of some covalent chemical bonds in the liquid. These bonds give rise in the power spectrum of the system dynamics to a well identifiable feature associated with stretching vibrations. The single-particle electronic density of states shows metallic behavior. The calculated electronic conductivity agrees well with the available experimental information.