Dynamical LEED study of $\mathrm{Pd}\mathrm{}\left(111\right)-(\sqrt{3}\times \sqrt{3})R30\mathrm{}°-\mathrm{Xe}$

A low-energy electron diffraction (LEED) study of $\mathrm{Pd}\mathrm{}\left(111\right)-(\sqrt{3}\times \sqrt{3})R30\mathrm{}°-\mathrm{Xe}$ at 77 K indicates that the Xe adsorption site is on top of the Pd atoms. The Xe–Pd bond length is $3.07\AA \pm 0.06\AA .$ The substrate structure is essentially unrelaxed from the bulk structure. These results contrast with an earlier spin-polarized LEED study, which indicated that hollow sites are occupied in this structure. The low-coordination-site geometry for Xe on Pd(111) is discussed in the context of earlier experimental studies and recent density functional theory results for Xe adsorption on metal surfaces.