Analytical interactomic potential for a molybdenum-erbium system

摘要

Analytical interatomic potentials of a molybdenum-erbium (Mo-Er) system are developed based on a Tersoff-Brenner-type form. The potentials well describes the bulk and defect properties of bcc Mo, including lattice parameter, cohesive energy, elastic constants, formation energies of point defects, surface energies and melting point. The adsorption behavior of Er on a Mo (1 1 0) surface is studied using ab initio calculations based on the density functional theory, which is used to fit the interatomic potential of a Mo-Er interaction. The growth mechanism of the Er film on a Mo substrate is investigated using the present potentials. The simulation results show that the microstructures and morphologies of Er films are sensitive to substrate temperatures. Columnar grains of hexagonal close-packed Er parallel to a Mo (1 1 0) surface are observed and the grain sizes increase with increasing substrate temperature.