The role of gold adatoms in self-assembled monolayers of thiol on Au(111)
E. Torres, A. T. Blumenau, P. U. Biedermann.
International Journal of Quantum Chemistry, 109, 3466 - 3472, (2009)
The role of Au adatoms in high-density alkanethiol self-assembled monolayers (SAMs) has been investigated. Surface reconstructions in ethylthiol (ET) SAMs due to gold adatoms have been studied using DFT calculations. Relative energies are compared based on binding and surface energies calculated for different lattices using the same unit cell. We have found a structure with two ET-Au-ET adatom moieties binding on top of surface gold atoms as the most stable structure. Our model is consistent with the structural parameters obtained from experiments. In particular, the simulated STM image displays the characteristic zig-zag pattern. (C) 2009 Wiley Periodicals, Inc. Int J Quantum Chem 109:3466-3472, 2009
Keyword(s): thiol gold self-assembled monolayers; DFT; binding site; surface reconstruction; gold adatoms