Potential energy surface and dynamics of Pd/MgO(001) system as investigated by periodic density functional calculations and classical molecular dynamics simulations

This study is the first attempt to establish reliable interatomic potential parameters for the two-body classical force field from the interaction energies of the Pd₁/MgO(001) interface obtained by the periodic density functional (DFT) calculations. Using these parameters, we can simulate the potential energy surface (PES) of the Pd₁/MgO(001) system and its dynamic behavior in a shorter time, using the classical molecular dynamics (MD) method. The fitted PES of the Pd₁/MgO(001) system obtained using the present parameters suggests the appearance of a saddle point during the migration of the Pd adatom on the fourfold hollow site. The dynamic behavior of the Pd adatom on the MgO(001) surface was also simulated by the classical MD method using the present parameters. These results agreed well with both the saddle point and the migration path of the adatom which was previously predicted by the Car-Parinello method.