Determination of the structure of Cu{1 0 0}–c(4×4)-In by TLEED

Tensor low energy electron diffraction (LEED) has been used to study the structure of In adsorbed on Cu{1 0 0} surface at a coverage of 0.60±0.03 ML. At this coverage, a c(4×4) ordered surface structure is formed. The favoured structure is an overlayer in which the two top layers are pure indium. The indium layer closest to bulk has a c(2×2) periodicity, in which In atoms lie at fourfold hollow sites with respect to the substrate. This c(2×2)-In layer is overlayered by a c(4×4) layer in which indium atoms lie at fourfold hollow sites with respect to the c(2×2)-In layer. Indium atoms in the c(2×2)-In layer are laterally shifted off the hollow sites towards bridge sites by 0.28±0.09 إ. Pendry reliability factor has been used to measure the level of agreement between theory and experiment giving a value of 0.28 for the favoured structure.