The structural analysis of Cu(111)-Te ([radical]3 x [radical]R30[degrees] and (2[radical]3 x 2[radical]3)R30[degrees] surface phases by quantitative LEED and DFT

The chemisorption of tellurium on atomically clean Cu(111) surface has been studied under ultra-high vacuum conditions. At room temperature, the initial stage of growth was an ordered (2[radical]3 x 2[radical]3)R30[degrees] phase (0.08 ML). An ordered ([radical]3 x [radical]3) R30[radical] phase is formed at 0.33 ML coverage of Te. The adsorption sites of the Te atoms on the Cu(111) surface at 0.08 ML and 0.33 ML coverages are explored by quantitative low energy electron diffraction (LEED) and density functional theory (DFT). Our results indicate that substitutional surface alloy formation starts at very low coverages.