Double stripe reconstruction of the Pt(111) surface

摘要

We have studied the reconstruction of the Pt(111) surface theoretically, using a 2D generalization of the Frenkel-Kontorova model. The parameters in the model are obtained by performing ab initio density functional theory calculations. The Pt(111) surface does not reconstruct under normal conditions but experiments have shown that there are two ways to induce the reconstruction: by increasing the temperature, or by depositing adatoms on the surface. The basic motif of this reconstruction is a 'double stripe' with an increased surface density and alternating hcp and fcc domains, arranged to form a honeycomb pattern with a very large repeat distance of 100-300 A. In this paper, we have studied the 'double stripe' reconstruction of the Pt(111) surface. In agreement with experiment, we find that it is favourable for the surface to reconstruct in the presence of adatoms, but not otherwise.