Atomic structure of chemisorbed iodine layer on Cu(1 1 0)

The adsorption of iodine on Cu(1 1 0) has been studied with scanning tunnelling microscopy and low energy electron diffraction. A simple commensurate structure c(2 × 2) is formed at the coverage θ = 0.5 ML. Further adsorption of iodine leads to the uniaxial compression of the c(2 × 2) structure along 〈1 1 0〉 direction of the substrate. STM data show that the compression includes the formation and development of striped domain walls. At the saturation point (θ = 0.63 ML), iodine forms a uniformly compressed quasi-hexagonal structure.