PHOTOELECTRON DIFFRACTION EVIDENCE FOR A SURFACE SUBSTITUTIONAL SITE OF SB IN THE SB-INDUCED SMOOTH GROWTH OF AG ON AG(111)

We apply low-energy photoelectron diffraction to study the crystalline site of Sb, either-adsorbed onto Ag(111) or segregated on its surface after silver homoepitaxy. The experimental data are-interpreted in th e framework of full multiple-scattering theory with complex potentials for different Sb positions. We conclude in favor of a surface substit ution site for Sb, and we also draw some conclusions about the Sb-Sb e nvironment. Our findings seem to corroborate the suggestion put forwar d by Vrijmoeth et al. [Phys. Rev. Lett. 72, 3843 (1994)] regarding the Sb-induced smooth growth of Ag on Ag(111).