Self-Assembly of Linear Three-Ring Aromatic Thiols on Au(111)

High Resolution Image Download MS PowerPoint Slide We report on the self-assembly of linear three-ring aromatic thiols on Au(111)/mica substrates. Our study examines terphenylthiol (TPT) derivatives with distinct terminal groups −F (FTPT), −CF 3 (CF 3 TPT) and −NO 2 (NTPT) as well as a pyridinebiphenyl (PyBPT) compound. Using complementary surface science techniques─X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), and scanning tunneling microscopy (STM)─we elucidate the structural properties of the resulting self-assembled monolayers (SAMs). The TPT, FTPT, CF 3 TPT and PyBPT molecules form densely packed SAMs with hexagonal unit cells exhibiting an area of 21.55 Å 2 per molecule. For the NTPT SAM, two different molecular arrangements were observed to coexist: a hexagonal structure and a squared structure, with areas per molecule of 21.55 and 42.25 Å 2, respectively.