Low-Energy-Electron-Diffraction Determination of the Atomic Arrangement in a Monatomic Underlayer of Nitrogen on Ti(0001)

Abstract

The importance of recognizing a 1 \ifmmode\times\else\texttimes\fi{} 1 structure preceding a superstructure in a chemisorption experiment is demonstrated by the system N-Ti(0001). Low-energy-electron-diffraction analysis of the 1 \ifmmode\times\else\texttimes\fi{} 1 structure reveals that the N atoms are located in the octahedral holes 1.22\ifmmode\pm\else\textpm\fi{}0.05 \AA{} below the first layer of Ti atoms. Interatomic distances are such as to justify the view of the surface structure as a single double-layer of TiN.