Self-assembled monolayers of a novel diacetylene on gold

We report on the preparation and characterization of self-assembled monolayers (SAMs) of a novel diacetylene monomer, the 14-N-carbazolyltetradeca-10,12-diyndisulfide. The SAM/gold interface was investigated by means of spectroscopic ellipsometry (SE), X-ray photoelectron spectroscopy (XPS) and scanning tunnelling microscopy (STM). SE data indicate a layer thickness compatible with the formation of a monomolecular layer. The occurrence of molecular chemisorption is confirmed by XPS measurements which indicate the formation of a thiolate species. This result is confirmed by STM imaging which shows the formation of small pits, one gold layer deep, a typical feature of self-assembled organosulfur monolayers on gold.