We describe theoretical calculations applying a 2D Frenkel-Kontorova (FK) model to the heteroepitaxial system Cu on Ru(1000). The experimentally observed variation of structure with layer thickness is simulated by scaling the adatom-adatom interaction. The minimum energy configurations are in exceptional agreement with recent scanning tunneling microscopy results showing four distinct structures as a function of thickness. These metal on metal films present a new realization of the FK model which complements previous investigations of rare gas adsorption on graphite.

• Received 27 February 1995

DOI:https://doi.org/10.1103/PhysRevLett.75.882