Structure and thermodynamics of liquid ruthenium and ruthenium-based alloys from ab initio and classical molecular dynamics with embedded atom model potentials

The combination of classical and ab initio molecular dynamics simulations for computing structural and thermodynamic properties of metallic liquids is illustrated on the example of ruthenium and ruthenium-based alloys. The classical simulations used embedded atom model (EAM) potentials parametrized with the force matching method. The ab initio reference data were obtained using two electronic structure codes implementing the density functional theory plane wave/pseudopotential method. Several methodological aspects in the determination of structural and thermodynamic properties in the liquid phase are examined, first for pure ruthenium. The efficiency of this combined method is finally illustrated on the structure and the pressure of ternary alloys of platinum group metals of interest in the treatment of nuclear wastes.