The structure of Cu{100}-p(2 × 6)-2mg-Sn studied by DFT and LEED

►A new model structure for 0.33 ML Cu{100}-p(2 × 6)-2mg-Sn system is presented. ►LEED and DFT have been used to analyse this structure at room temperature. ►The favoured geometry is a combination of an overlayer structure and a surface alloy.