Collective motion and oscillatory interaction: –Cu–O– and sulfite on Cu(<f>1 1 0</f>)

Our STM investigation of oxygen and sulfite on the Cu(1 1 0) surface suggests that chains of –Cu–O– and Cu–SO3 migrate via collective motion. The minimum diffusivities of the –Cu–O– and Cu–SO3 chains have been calculated to be (<f>4.5±2.5)×10−14</f> cm2/s and (<f>7.2±1.8)×10−14</f> cm2/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(<f>2×1</f>)-O islands and a migrating –Cu–O– chain. Amid p(<f>2×1</f>)-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(<f>2×1</f>)-O island. A chain migrating in-between p(<f>2×1</f>)-O islands not separated by a multiple of two lattice units from one another does not prefer one site over another. [Copyright &y& Elsevier]