Surface Structure of N/Pd(100)-c(2×2) Determined by Tensor Low Energy Electron Diffraction Analysis

The surface structure of N/Pd(100)- c (2×2) was investigated by means of the tensor low energy electron diffraction I – V analysis. The N atom was found to adsorb at the fourfold hollow site facing downward at a distance of 0.13±0.07 Å with respect to the first Pd layer. A slight buckling of the second Pd layer was also noticed, and the buckled distance was estimated to be 0.08±0.07 Å. The N atom is consequently coordinated by one second-layer Pd atom with the N–Pd distance of 2.02×0.07 Å as well as four first-layer Pd atoms with the N–Pd distance of 1.96±0.02 Å. Fivefold coordination observed in the present system is similar to the case of N/Ni(100)-p4g(2×2), although no reconstruction takes place on Pd(100).