title: Self-organization of S adatoms on Au(111): √3R30° rows at low coverage.
abstract: Using scanning tunneling microscopy, we observe an adlayer structure that is dominated by short rows of S atoms, on unreconstructed regions of a Au(111) surface. This structure forms upon adsorption of low S coverage (less than 0.1 monolayer) on a fully reconstructed clean surface at 300 K, then cooling to 5 K for observation. The rows adopt one of three orientations that are rotated by 30° from the close-packed directions of the Au(111) substrate, and adjacent S atoms in the rows are separated by √3 times the surface lattice constant, a. Monte Carlo simulations are performed on lattice-gas models, derived using a limited cluster expansion based on density functional theory energetics. Models which include long-range pairwise interactions (extending to 5a), plus selected trio interactions, successfully reproduce the linear rows of S atoms at reasonable temperatures.
authors.affiliation: Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Holly
authors.initials: H
authors.lastname: Walen
authors.affiliation: Ames Laboratory of the USDOE, Ames, Iowa 50011, USA.
authors.forename: Da-Jiang
authors.initials: DJ
authors.lastname: Liu
authors.affiliation: RIKEN Surface and Interface Science Laboratory, Wako, Saitama 351-0198, Japan.
authors.forename: Junepyo
authors.initials: J
authors.lastname: Oh
authors.affiliation: RIKEN Surface and Interface Science Laboratory, Wako, Saitama 351-0198, Japan.
authors.forename: Hyunseob
authors.initials: H
authors.lastname: Lim
authors.affiliation: Ames Laboratory of the USDOE, Ames, Iowa 50011, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Evans
authors.affiliation: RIKEN Surface and Interface Science Laboratory, Wako, Saitama 351-0198, Japan.
authors.forename: Yousoo
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Thiel