Self-organized Gd atomic superlattice on Ag(111): Scanning tunneling microscopy and kinetic Monte Carlo simulations

► We experimentally demonstrate the Gd hexagonal superlattice on Ag(111) surfaces. ► The diffusion barrier and long-range interaction are determined experimentally. ► We discuss the mechanism and confirm the preconditions for superlattice formation. ► We predict that similar self-organization could form in other lanthanide adatoms.