Diffractive scattering of H atoms from an ordered xenon overlayer adsorbed on the (0001) surface of graphite

H-atom diffractive scattering was carried out from a ?3×?3 lattice of xenon atoms adsorbed on the (0001) surface of graphite. The experimental data are well reproduced by a hard-wall scattering model, both with and without a correction due to the attractive part of the potential, resulting in peak-to-peak corrugations of 1.07±0.05 and 1.19±0.05 Å, respectively. A realistic H-Xe-C(0001) potential, based on the assumption of pairwise additive atom-adatom interactions, is calculated and found to have a corrugation of 0.99±0.05 Å.