LEED structure determination of two ordered surface alloys: Cu(100)-c(2 × 2)Mn and Ni(100)-c(2 × 2)Mn

Abstract

The structure of the Cu(100)-c(2 × 2)Mn and Ni(100)-c(2 × 2)Mn phase was determined by a quantitative low-energy electron diffraction (LEED) intensity analysis. These structures are ordered surface alloys which form after deposition of 0.5 ML Mn on the clean Cu(100) and Ni(100) surface above 270 K. The alloy layer shows a pronounced corrugation in which Mn atoms in the first layer are displaced outwards by 0.30 ± 0.02 A ̊ on Cu(100) and 0.25 ± 0.02 A ̊ on Ni(100). The interlayer distance from the Cu (Ni) atoms to second layer Cu (Ni) atoms is close to the Cu(100)-[Ni(100)] bulk interlayer spacing of 1.807 Å (1.76 Å). Deeper interlayer distances are also very similar to the respective bulk value.