In, Sn dimers on Si(100)2×1 surface: ab initio calculations and STM experiments

Low dimensional systems and especially 1D systems can present very original properties. It is now well established that the deposition of Group III (Al, Ga, In) or IV (Si, Ge, Sn, Pb) atoms on the Si(100)2×1 surface results in the formation of lines of dimers. We have determined the geometry of Sn, In and In–Sn mixed dimers on Si(100)2×1 surface both from theoretical and experimental points of view. Ab initio calculations are performed with the generalized gradient correction to the local density approximation of the density functional theory. Theoretical results and ultrahigh vacuum (UHV) scanning tunneling microscopy (STM) images are compared and discussed in the light of simple arguments based on changes in the hybridization states of the orbitals of the surface ad dimer atoms.