SURFACE-STRUCTURE OF N PD(100)-C(2X2) DETERMINED BY TENSOR LOW-ENERGY-ELECTRON DIFFRACTION ANALYSIS/

The surface structure of N/Pd(100)-c(2 x 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 Angstrom with respect to the first Pd layer. A slight buckling of the second Pd layer was also noticed, and the buck led distance was estimated to be 0.08 +/- 0.07 Angstrom. The N atom is consequently coordinated by one second-layer Pd atom with the N-Pd di stance of 2.02 x 0.07 Angstrom as well as four first-layer Pd atoms wi th the N-Pd distance of 1.96 +/- 0.02 Angstrom. Fivefold coordination observed in the present system is similar to the case of N/Ni(100)-p4g (2 x 2), although no reconstruction takes place on Pd(100).