title: Surface morphology of atomic nitrogen on Pt(111).
abstract: The surface morphology of chemisorbed N on the Pt(111) surface has been studied at the atomic level with low temperature scanning tunneling microscopy (STM). When N is coadsorbed with O on the surface, they form a mixed (2 × 2)-N+O structure. When the surface is covered with N atoms only, isolated atoms and incomplete (2 × 2) patches are observed at low coverages. In a dense N layer, two phases, (√3 × √3)R30°-N and p(2 × 2)-N, are found to coexist at temperatures between 360 and 400 K. The (√3 × √3)R30° phase converts to the (2 × 2) phase as temperature increases. For both phases, nitrogen occupies fcc-hollow sites. At temperatures above 420 K, nitrogen starts to desorb. The p(2 × 2)-N phase shows a honeycomb structure in STM images with three nitrogen and three platinum atoms forming a six-membered ring, which can be attributed to the strong nitrogen binding to the underlying Pt surface.
authors.affiliation: Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, USA.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Liang
authors.affiliation: Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Yang
authors.affiliation: Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Yousoo
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Trenary