  We investigated the adsorption of iodine on silver (111) in ultra-high
vacuum. Using low-temperature scanning tunneling microscopy (LT-STM)
measurements we catalog the complex surface structures on the local scale. We
identified three distinct phases with increasing iodine coverage which we
tentatively associate with three phases previously reported in LEED experiments
(sqrt(3)x sqrt(3)R30, "triangular", "hexagonal"). We used Fourier space and
real space analysis to fully characterize each phase. While Fourier analysis
most easily connects our measurements to previous LEED studies, the real space
inspection reveals local variations in the superstructures of the "hexagonal"
and "triangular" phase. The latter, observed here for the first time by LT-STM,
stabilized by one or two adatoms sitting at the center of a rosette-like iodine
reconstruction. The most stunning discovery is that variation in the adatom
separation of the "triangular" phase reconstruct the Ag (111) surface lattice.
