The melting transition of Ce adatom superlattices stabilized by long-range substrate-mediated electronic interactions on Cu(111) and Ag(111) noble metal surfaces has been investigated by low-temperature scanning tunneling microscopy, density functional theory calculations, and kinetic Monte Carlo simulations. Intriguingly, owing to the interaction between Ce adatoms and substrate, these superlattices undergo two-dimensional melting to a liquid without transition through the hexatic phase. The crucial parameters for this direct solid to liquid transition are identified.
Michele Ceriotti, Guillaume André Jean Fraux, Arslan Mazitov, Sandip De, Nataliya Lopanitsyna