  Low energy electron diffraction (LEED), scanning tunneling microscopy (STM),
and photoelectron spectroscopy have been used to study an ordered structure
formed by Ge atoms deposited onto the Au(111) surface. Based on a careful
analysis of STM images and LEED patterns, we propose a new unit cell for the
atomic structure of the Ge layer. Core level data indicate that some Ge atoms
diffuse into the Au(111) crystal during annealing after deposition at room
temperature. This is further corroborated by angle resolved photoelectron
spectroscopy measured for different amounts of Ge remaining after sputtering
and annealing. The results of the ARPES study clearly exclude the
interpretation, in the literature, of a parabolic band as part of a Dirac cone
of germanene.
