A van der Waals DFT study of chain length dependence of alkanethiol adsorption on Au(111): physisorption vs. chemisorption

Mete, Ersen
Yortanli, Merve
Danışman, Mehmet Fatih
The energetics and structures of physisorbed and chemisorbed alkanethiols on Au(111) have been systematically investigated up to 10 carbon atoms using van der Waals (vdW) corrected density functional theory (DFT) calculations. The role of chain length, tilting angle and coverage on the adsorption characteristics has been examined to elucidate the energetics and plausible transformation mechanisms between lying down and standing up phases. Coverage and size dependent chain-chain electronic interactions counteract with the alkyl chain-gold surface interactions and the surface relaxation of the metal in the formation of standing up monolayer structures. For the striped phases of long chain alkanethiols, however, our calculations on decanethiol indicate alkyl chain-gold surface interactions to be strong enough to force the molecule to be perfectly parallel to the surface by lifting a gold atom up, in agreement with the proposed models for this film in the literature.


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Yılmaz, Ayşen; Danışman, Mehmet Fatih (2016-05-14)
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A DFT Study of Direct Oxidation of Benzene to Phenol by N2O over [Fe(mu-O)Fe](2+) Complexes in ZSM-5 Zeolite
Fellah, Mehmet Ferdi; Pidko, Evgeny A.; van Santen, Rutger A.; Önal, Işık (2011-05-19)
Density functional theory (DFT) calculations were carried out in a study of the mechanism of benzene oxidation by N2O to phenol over an extra framework dimeric [FeOFe](2+) species in ZSM-5 zeolite represented by a [Si6Al2O9H14(Fe(mu-O)Fe)] cluster model. The catalytic reactivity of such a binuclear species is compared with that of mononuclear Fe2+ and (FeO)(+) sites in ZSM-5 investigated in our earlier works at the same level of theory (J. Phys. Chem. C 2009, 113, 15307; 2010, 114, 12580). The activation en...
A Density Functional Theory Study of Direct Oxidation of Benzene to Phenol by N2O on a [FeO](1+)-ZSM-5 Cluster
Fellah, Mehmet Ferdi; Önal, Işık; van Santen, Rutger A. (2010-07-29)
Density functional theory calculations were carried out in a study of the oxidation of benzene to phenol by N2O on a model (FeO)(1+)-ZSM-5 cluster: the [(SiH3)(4)AlO4(FeO)] cluster. This cluster models the reactivity of Fe3+ oxidic clusters. Results are to be compared with an earlier study (J. Phys. Chem. C 2009, 113, 15307) on a model Fe2+-ZSM-5 cluster. The true activation energies for the elementary reaction step in which phenol is produced appear to be comparable. The major difference between the two sy...
Citation Formats
E. Mete, M. Yortanli, and M. F. Danışman, “A van der Waals DFT study of chain length dependence of alkanethiol adsorption on Au(111): physisorption vs. chemisorption,” PHYSICAL CHEMISTRY CHEMICAL PHYSICS, pp. 13756–13766, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42163.