Observation of ordered structures for S/Cu(111) at low temperature and coverage

Via scanning tunneling microscopy and low energy electron loss diffraction we observe ordered low-temperature surface structures for S/Cu(111) at low-S coverage and characterize the system also with core level photoemission. The first structure to appear upon S deposition is honeycomblike with a large mesh [(√43×√43)R±7.5^∘], a large nearest S-S distance (~4) and low-ordering temperature (<170K). Islands of this structure are observed at low coverage (θ~0.05) and at θ~0.25 nearly all of the surface area is covered.