Towards an understanding of surfactant action in the epitaxial growth of metals: The case of Sb on Ag (111)

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Sb gains only about 0.2 eV by being lifted to the upper layer by exchange with asingle Ag from the upper layer. One thus expects that to create on-surface Sb at an appreciable rate from substitutional Sb, more upper-layer Ag neighbors are needed to provide sufficient coordination to the Sb atom being lifted

Indeed, recent STM results indicate the presence of Sb not only on the substrate, but also on the growing islands ([10], and private communication by J. Meyer)