Annealed decanethiol monolayers on Au(111) – intermediate phases between structures with high and low molecular surface density

Self-assembled monolayers of decanethiol on Au(111) have been investigated using high resolution scanning tunneling microscopy (STM). After the annealing of the as-adsorbed densely packed c(23×43)R30° structure and before the formation of a previously described low density (11.5×3) stripe phase three different phases with intermediate molecular surface density have been observed. We present highly resolved and distortion-corrected STM images for both the (7.5×3) stripe phase and the meshlike structure. We describe a mixed (7.5/11.5×3) stripe phase that shows a switching of the stripe arrangement.