Structure analysis of Cu(0 0 1)–c(4 × 4)-In by surface X-ray diffraction

The structure of the Cu(0 0 1)–c(4 × 4)-In surface has been studied with surface X-ray diffraction. The surface structure model that has previously been proposed based on the low energy electron diffraction (LEED) analysis consists of two indium layers. The present results support the proposed structure model as to the lateral arrangement. The difference was found in the vertical spacing between the indium layers. The distance was determined to be 0.18 Å, which shows the overlayer structure like a dense single-atomic layer with a small vertical relaxation rather than the bilayer structure proposed by LEED.