Surface alloy in the c(4 × 4) phase of Pb on Cu(100)

Gauthier, Y.; Moritz, Wolfgang and Hösler, W. (1996): Surface alloy in the c(4 × 4) phase of Pb on Cu(100). In: Surface Science, Vol. 345, No. 1-2: pp. 53-63

Abstract

The structure of the c(4 × 4) phase of Pb on Cu(100) has been determined by a LEED I/V analysis. The characteristic feature of this structure are Pb chains along the close packed rows with Cu chains between the Pb chains. The surface layer is an ordered alloy layer with 3 Pb and 4 Cu atoms in the primitive unit cell, the Pb coverage is 0.375 monolayers. The Pb-Pb distance within the chain is 3.4 Å and 2.8\% smaller than the distances in bulk Pb. The Pb chain is slightly corrugated by 0.05 Å where one of the three Pb atoms is in a hollow site of the substrate. Due to the smaller atomic radius the Cu chain is 0.65 Å below the Pb site. Half of the Cu atoms are shifted by 0.23 Å off the fourfold sites such that roughly the same distance to the surrounding Pb atoms in the top layer is maintained. The Pb-Cu bond length varies slightly at different sites around 2.9 Å.

• Item Type: Journal article
• Faculties: Geosciences > Department of Earth and Environmental Sciences > Crystallography and Materials Science
• Subjects: 500 Science > 550 Earth sciences and geology
• Language: English