Self-Assembly of One-Dimensional Surface Structures: Long-Range Interactions in the Growth of Ir and Pd on W(110)

Self-assembly of one-dimensional surface structures is examined by tracking single Ir and Pd atoms on W(110) as they incorporate into chains of Ir and Pd, respectively. Ir adatoms move parallel to the chains, but do not come close to the chain sides; incorporation occurs only at the ends. Pd adatoms also migrate parallel to Pd chains, and incorporate at the ends. Occasionally, in the end region, they do jump to the side of a chain, and migrate there until they find an end site. Incorporation behavior for both Ir and Pd is driven by highly anisotropic, long-ranged interactions between atoms on the surface.