AVS 60th International Symposium and Exhibition
    Surface Science Wednesday Sessions
       Session SS+AS+NS+SP-WeA

Paper SS+AS+NS+SP-WeA9
Surface Morphology of Chemisorbed N on Pt(111)

Wednesday, October 30, 2013, 4:40 pm, Room 202 A

Session: Single Molecules at Surfaces: Structure and Dynamics
Presenter: Z. Liang, University of Illinois at Chicago
Authors: Z. Liang, University of Illinois at Chicago
H. Yang, RIKEN, Japan
Y. Kim, RIKEN, Japan
M. Trenary, University of Illinois at Chicago
Correspondent: Click to Email
The surface morphology of chemisorbed N on a Pt(111) surface has been studied at the atomic level with low temperature scanning tunneling microscopy (LT-STM). At high coverages, two phases, p(2×2)-N and (√3×√3)R30°-N, are found to coexist at temperatures between 360 and 400 K. For both phases nitrogen occupies fcc-hollow sites. At temperatures of 400 K and slightly above, only the p(2×2)-N phase is present on the surface. At temperatures above 420 K, nitrogen starts to desorb. The p(2×2)-N phase shows a honey-comb structure in STM images with three nitrogen and three platinum atoms forming a six-member ring, which can be attributed to the strong nitrogen binding to the underlying Pt atoms. At low coverages, incomplete (2×2) patches of N, but no (√3×√3)R30° structure, are observed on the surface. When N and O are coadsorbed on the surface, they form a mixed (2×2) overlayer of N+O at high coverages. N and O can be clearly distinguished from each other by their appearance in the STM images.