Apparent charge transfer at theGexPb1−x/Ge(111)interface

We investigate the apparent charge transfer between adatoms in the ${\mathrm{Ge}}_x{\mathrm{Pb}}_{\left(1\mathrm{}-x\right)}/\mathrm{Ge}\mathrm{}\left(111\right)\mathrm{}$ interface both experimentally and theoretically. Scanning tunneling microscopy and surface core-level measurements suggest significant charge transfer from the Ge adatoms to the Pb adatoms. However, first-principles calculations unambiguously find that the total electronic displacement is negligibly small and that the results of published experiments can be explained as a result of bond rearrangement.