STM Study of Self-Organization of 10CB Molecules on Au(111) Surface

Abstract

We report the scanning tunnelling microscopy (STM) observation of a self-organization of 4-cyano-4′-n-decylbiphenyl (10CB) molecules on the reconstructed Au(111) surface. The self-organized monolayers were obtained by the deposition from a liquid. We revealed a row-like dimer structure with regularly arranged kinks within each dimer row. The separation between neighbor kinks is equal to 4 or 5 intermolecular distances. STM-images with intramolecular resolution showed that the association of molecules in dimers is due to the interaction between cyano groups. The obtained results are discussed in terms of the balance between the molecule-molecule and molecule-substrate interactions and are supported by the results of DFT calculations.

Keywords:

• STM
• self-assembled monolayers
• reconstructed Au(111) surface
• 10CB
• 4-cyano-4′-n-decylbiphenyl
• alignment
• alkyl chain