Confinement effects on the growth of adsorbates: Interpretation of the formation of monoatomic Ag wires on Pt(997)

Kinetic Monte Carlo simulations based on semiempirical description of metal-metal interactions are developed to interpret recent experiments devoted to the formation of silver wires at the steps of the vicinal Pt(997) surface. The growth mode of Ag on the terraces is discussed as a function of external parameters tied to experimental conditions (coverage, temperature, deposition flux) and of intrinsic parameters characterizing the lateral interactions and the properties of the confined surface through the knowledge of Ag-Ag and Ag-Pt interactions. According to the external conditions, the growth mode is shown to obey a row-by-row plus island process or a fractal island formation at the step, in very good agreement with the data of helium atom scattering and tunneling microscopy.