The dynamic behavior of butanethiol and dodecanethiol adsorbates on Au(111) terraces

The dynamics of butanethiol and dodecanethiol monolayers adsorbed on Au(111) studied by ex situ and in situ sequential scanning tunneling microscopy (STM) shows, at room temperature and in the range of seconds, √3×√3 R30°⇔c(4×2) transitions. High-resolution STM imaging also shows that these transitions can be explained by a displacement of adsorbed molecules from hollow to bridge sites and vice versa. Transitions from the p(n×1) superlattice to the √3×√3 R30° lattice were also imaged in real time. These processes appear to be coupled with fluctuations of the hole size of the Au(111) terrace.