Our STM investigation of oxygen and sulfite on the Cu(1 1 0) surface suggests that chains of -Cu-O- and Cu-SO 3 migrate via collective motion. The minimum diffusivities of the -Cu-O- and Cu-SO 3 chains have been calculated to be (4.5±2.5)×10 -14 cm 2/s and (7.2±1.8)×10 -14 cm 2/s, respectively. The time a -Cu-O- row spends in a particular site provides evidence for the oscillatory nature of the interaction energy between p(2×1)-O islands and a migrating -Cu-O- chain. Amid p(2×1)-O islands spaced a multiple of two lattice units from one another, the -Cu-O- chains have a preference for sites which are a multiple of two lattice units from a nearby p(2×1)-O island. A chain migrating in-between p(2×1)-O islands not separated by a multiple of two lattice units from one another does not prefer one site over another.