Ag adatom and dimer motion on Cu(1 1 0)(1 × 2) missing row surface

The diffusion of Ag monomer and dimer on Cu(1 1 0)(1 × 2) missing row reconstructed surface is investigated by using the molecular dynamics simulation based on semi-empirical many-body potentials derived from the embedded atom method. In the case of monomer diffusion, both simple jump and long jump follow an Arrhenius law in a large temperature range (300-500 K) but with a small difference in activation energy. The activation barrier energy for simple jump is found to be (0.27 ± 0.02) eV with corresponding prefactor 5.9 ps−1. However, for double jump we found Ea2 = (0.33 ± 0.05) eV. While in the case of dimer, we found that the adatoms activity is notably reduced at low temperature (T < 400 K) and the diffusion via dissociation-reassociation process is more favoured than the other processes. This finding is in a good agreement with the energetic prediction. The presence of concerted jump and leapfrog process is very rare due to their high corresponding activation energy.