Jump to main content
Jump to site search

Issue 20, 2011
Previous Article Next Article

Theoretical study of the structure of self-assembled monolayers of short alkylthiolates on Au(111) and Ag(111): the role of induced substrate reconstruction and chain–chain interactions

Author affiliations

Abstract

We compare the stability of various structures of high coverage self-assembled monolayers (SAMs) of short alkylthiolates, S(CH2)n−1CH3 (= Cn), on Ag(111) and Au(111). We employ: (i) the ab initio thermodynamics approach based on density functional theory (DFT) calculations, to compare the stability of SAMs of C1 (with coverages Θ = 3/7 and 1/3) on both substrates, and (ii) a set of pairwise interatomic potentials derived from second-order Møller-Plesset (MP2) perturbation theory calculations, to estimate the role of chain–chain (Ch–Ch) interactions in the structure and stability of SAMs of longer chain alkylthiolates. For C1/Ag(111) (C1/Au(111)) the SAM with Θ = 3/7 is more (less) stable than for Θ = 1/3 in a wide range of temperatures and pressures in line with experiments. In addition, for the molecular densities of SAMs corresponding to Θ = 3/7 and 1/3, the MP2-based Ch–Ch interaction potential also predicts the different chain orientations observed experimentally in SAMs of alkylthiolates on Ag(111) and Au(111). Thus, for short length alkylthiolates, a simple model based on first principles calculations that separately accounts for molecule–surface (M–S) and Ch–Ch interactions succeeds in predicting the main structural differences between the full coverage SAMs usually observed experimentally on Ag(111) and Au(111).

Graphical abstract: Theoretical study of the structure of self-assembled monolayers of short alkylthiolates on Au(111) and Ag(111): the role of induced substrate reconstruction and chain–chain interactions

Back to tab navigation

Article information


Submitted
10 Nov 2010
Accepted
08 Mar 2011
First published
09 Apr 2011

Phys. Chem. Chem. Phys., 2011,13, 9353-9362
Article type
Paper

Theoretical study of the structure of self-assembled monolayers of short alkylthiolates on Au(111) and Ag(111): the role of induced substrate reconstruction and chain–chain interactions

P. N. Abufager, J. G. Solano Canchaya, Y. Wang, M. Alcamí, F. Martín, L. Alvarez Soria, M. L. Martiarena, K. Reuter and H. F. Busnengo, Phys. Chem. Chem. Phys., 2011, 13, 9353
DOI: 10.1039/C0CP02490B

Social activity

Search articles by author

Spotlight

Advertisements