Potential-induced strain relaxation in au mono- and bilayer films on Pt(111) electrode surfaces.
In situ scanning tunneling microscopy observations of 1-2 monolayer thick Au films on Pt(111) electrodes are presented, which show a complex, potential-dependent structural phase behavior of the Au film. Starting from a pseudomorphic structure at <0.35 V(Ag/AgCl), a sequence of transitions into dislocation network structures occurs with increasing potential: (1x1)--> "striped phase" --> "hex phase" in the Au bilayer, (1x1)--> striped phase in the Au monolayer. This is explained by a reduction of the in-plane stress in the Au surface layer(s) due to anion adsorption and a strain energy minimization as described by the Frenkel-Kontorova model.
Sibert
E
E
Abteilung Oberflächenchemie und Katalyse, Universität Ulm, Germany.
Ozanam
F
F
Maroun
F
F
Magnussen
O M
OM
Behm
R J
RJ