The article is the result of a collaboration between French researchers from CNRS (Institut des NanoSciences of Paris and CINaM of Marseille), synchrotron facility SOLEIL and Italian researchers from CNR-ISM.
The two-dimensional structures of silicon on Ag (110) were studied by grazing incidence X-ray diffraction and scanning tunneling microscopy. The thermodynamic stability of different structural models has been explored by ab initio theoretical calculations The combination of these experimental and theoretical techniques has allowed us to demonstrate that, by adding silicon atoms to the pentameric structures called nanoribbons that are formed by depositing silicon on Ag (110), these one-dimensional structures evolve into a two-dimensional silicene single layer. Finally, a further slight increase of deposited silicon gives rise to the formation of dumbbell silicene, in which the presence of silicon adatoms regularly distributed on the silicene layer results in a further stabilization of the two-dimensional silicon structure.