Energetics and structures of Pt, Pd, and Ni adatom clusters on the Pt(001) surface

In this paper using the embedded atom method (EAM), the authors calculated the stable configurations of Pt, Pd, and Ni clusters, containing up to nine adatoms, on the Pt (001) surface. For Pt, we predict that the stable configurations are linear chains oriented along the < 110 > directions for three and five adatoms, and close-packed islands otherwise. For Pd, the results are the same except that the stable configuration predicted for five adatoms is a close-packed island. For Ni, the authors predict that linear chains are the stable configurations for all numbers of adatoms. In determining these stable configurations, we allowed substrate relaxations. To assess the importance of substrate relaxations, we also performed calculations on an unrelaxed substrate. The authors found that substrate relaxations are important with regard to the stable configurations, and that allowing relaxation lowers the energies of chains with respect to islands