Ab initio modeling of the local violation of a Peierls transition at the Sb(111) surface

The crystal structure of the Sb(111) surface is studied within the density functional theory. It is shown that a defect near-surface region with a thickness of 6–8 atomic layers, which is similar to a topological soliton in hydrocarbon one-dimensional chains, is formed at the surface because of the break of bilayers. The formation of the defect layer is discussed within the Su–Schrieffer–Heeger model in terms of the local violation of the Peierls transition.