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Title: Self Assembly of 1,4-Benzenediothiolate-Tetrahydrofuran Mixtures on Gold surface: A Monte Carlo Simulation Study

Abstract

We report a Monte Carlo simulation study of the self-assembly of 1,4-benzenedithiolate (BDT), tetrahydrofuran (THF), and their mixtures on a Au (111) surface. We use the grand canonical Monte Carlo method to obtain the equilibrium adsorption coverage. Canonical ensemble (NVT) simulation is then used to explore further the structural information of the equilibrated systems. Our results indicate that BDT molecules adsorb onto the Au (111) surface with one of the sulfur atoms bonded to Au atoms. THF molecules form clusters on the surface. For BDT?THF mixtures, BDT can selectively adsorb on Au (111) to form a monolayer, whereas the solvent THF molecules either float above BDT monolayer or occupy vacancies on the surface that are not covered by BDT molecules. BDT molecules adsorb on a Au (111) surface with an average tilt angle of about 18-35{sup o} to the surface normal. The tilting angle decreases as the coverage increases. In addition, the BDT monolayer constitutes an ordered herringbone structure on the Au (111) surface, and the ordering pattern is insensitive to the BDT coverage. In comparison, the THF molecules exhibit amorphous structure on the Au surface. Interestingly, simulations indicate that the bonding behavior of BDT molecules on Au (111) ismore » coverage-dependent. BDT bonds preferably on the Au top site when the surface coverage is low. As coverage increases, most BDT molecules bond on the bridge and fcc hollow sites.« less

Authors:
 [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS); Center for Computational Sciences
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
944942
DOE Contract Number:
AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Langmuir; Journal Volume: 22; Journal Issue: 9
Country of Publication:
United States
Language:
English

Citation Formats

Zhao, Xiongce, Leng, Yongsheng, and Cummings, Peter T. Self Assembly of 1,4-Benzenediothiolate-Tetrahydrofuran Mixtures on Gold surface: A Monte Carlo Simulation Study. United States: N. p., 2006. Web. doi:10.1021/la0532252.
Zhao, Xiongce, Leng, Yongsheng, & Cummings, Peter T. Self Assembly of 1,4-Benzenediothiolate-Tetrahydrofuran Mixtures on Gold surface: A Monte Carlo Simulation Study. United States. doi:10.1021/la0532252.
Zhao, Xiongce, Leng, Yongsheng, and Cummings, Peter T. Sun . "Self Assembly of 1,4-Benzenediothiolate-Tetrahydrofuran Mixtures on Gold surface: A Monte Carlo Simulation Study". United States. doi:10.1021/la0532252.
@article{osti_944942,
title = {Self Assembly of 1,4-Benzenediothiolate-Tetrahydrofuran Mixtures on Gold surface: A Monte Carlo Simulation Study},
author = {Zhao, Xiongce and Leng, Yongsheng and Cummings, Peter T},
abstractNote = {We report a Monte Carlo simulation study of the self-assembly of 1,4-benzenedithiolate (BDT), tetrahydrofuran (THF), and their mixtures on a Au (111) surface. We use the grand canonical Monte Carlo method to obtain the equilibrium adsorption coverage. Canonical ensemble (NVT) simulation is then used to explore further the structural information of the equilibrated systems. Our results indicate that BDT molecules adsorb onto the Au (111) surface with one of the sulfur atoms bonded to Au atoms. THF molecules form clusters on the surface. For BDT?THF mixtures, BDT can selectively adsorb on Au (111) to form a monolayer, whereas the solvent THF molecules either float above BDT monolayer or occupy vacancies on the surface that are not covered by BDT molecules. BDT molecules adsorb on a Au (111) surface with an average tilt angle of about 18-35{sup o} to the surface normal. The tilting angle decreases as the coverage increases. In addition, the BDT monolayer constitutes an ordered herringbone structure on the Au (111) surface, and the ordering pattern is insensitive to the BDT coverage. In comparison, the THF molecules exhibit amorphous structure on the Au surface. Interestingly, simulations indicate that the bonding behavior of BDT molecules on Au (111) is coverage-dependent. BDT bonds preferably on the Au top site when the surface coverage is low. As coverage increases, most BDT molecules bond on the bridge and fcc hollow sites.},
doi = {10.1021/la0532252},
journal = {Langmuir},
number = 9,
volume = 22,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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