First-principles molecular dynamics of metallic systems

We present an efficient method to perform microcanonical first-principles m olecular-dynamics simulations on metallic systems. The method is based on a dynamical scheme for the electronic degrees of freedom, and uses a rotatio nally invariant finite temperature density functional. A strategy to handle electronic state occupancies is proposed. We show that the convergence to the electronic ground state and the dynamical properties of the scheme do n ot depend on the electronic gap of the system studied. The scheme is demons trated by simulations on aluminum systems. [S0163-1829(99)01843-3].