skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Mechanical and charge transport properties of alkanethiol self-assembled monolayers on Au (111) surface: The Role of Molecular Tilt

Abstract

The relationship between charge transport and mechanical properties of alkanethiol self-assembled monolayers (SAM) on Au(111) films has been investigated using an atomic force microscope with a conductive tip. Molecular tilts induced by the pressure applied by the tip cause stepwise increases in film conductivity. A decay constant {beta} = 0.57 {+-} 0.03 {angstrom}{sup -1} was found for the current passing through the film as a function of tip-substrate separation due to this molecular tilt. This is significantly smaller than the value of {approx} 1 {angstrom}{sup -1} found when the separation is changed by changing the length of the alkanethiol molecules. Calculations indicate that for isolated dithiol molecules S-bonded to hollow sites, the junction conductance does not vary significantly as a function of molecular tilt. The impact of S-Au bonding on SAM conductance is discussed.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
Materials Sciences Division
OSTI Identifier:
926165
Report Number(s):
LBNL-69E
Journal ID: ISSN 0743-7463; LANGD5; TRN: US200807%%503
DOE Contract Number:  
DE-AC02-05CH11231
Resource Type:
Journal Article
Journal Name:
Langmuir
Additional Journal Information:
Journal Volume: 24; Journal Issue: 5; Related Information: Journal Publication Date: 2008; Journal ID: ISSN 0743-7463
Country of Publication:
United States
Language:
English
Subject:
36; BONDING; CHARGE TRANSPORT; DECAY; DITHIOLS; MECHANICAL PROPERTIES; MICROSCOPES

Citation Formats

Mulleregan, Alice, Qi, Yabing, Ratera, Imma, Park, Jeong Y, Ashby, Paul D, Quek, Su Ying, Neaton, J B, and Salmeron, Miquel. Mechanical and charge transport properties of alkanethiol self-assembled monolayers on Au (111) surface: The Role of Molecular Tilt. United States: N. p., 2007. Web.
Mulleregan, Alice, Qi, Yabing, Ratera, Imma, Park, Jeong Y, Ashby, Paul D, Quek, Su Ying, Neaton, J B, & Salmeron, Miquel. Mechanical and charge transport properties of alkanethiol self-assembled monolayers on Au (111) surface: The Role of Molecular Tilt. United States.
Mulleregan, Alice, Qi, Yabing, Ratera, Imma, Park, Jeong Y, Ashby, Paul D, Quek, Su Ying, Neaton, J B, and Salmeron, Miquel. Mon . "Mechanical and charge transport properties of alkanethiol self-assembled monolayers on Au (111) surface: The Role of Molecular Tilt". United States. https://www.osti.gov/servlets/purl/926165.
@article{osti_926165,
title = {Mechanical and charge transport properties of alkanethiol self-assembled monolayers on Au (111) surface: The Role of Molecular Tilt},
author = {Mulleregan, Alice and Qi, Yabing and Ratera, Imma and Park, Jeong Y and Ashby, Paul D and Quek, Su Ying and Neaton, J B and Salmeron, Miquel},
abstractNote = {The relationship between charge transport and mechanical properties of alkanethiol self-assembled monolayers (SAM) on Au(111) films has been investigated using an atomic force microscope with a conductive tip. Molecular tilts induced by the pressure applied by the tip cause stepwise increases in film conductivity. A decay constant {beta} = 0.57 {+-} 0.03 {angstrom}{sup -1} was found for the current passing through the film as a function of tip-substrate separation due to this molecular tilt. This is significantly smaller than the value of {approx} 1 {angstrom}{sup -1} found when the separation is changed by changing the length of the alkanethiol molecules. Calculations indicate that for isolated dithiol molecules S-bonded to hollow sites, the junction conductance does not vary significantly as a function of molecular tilt. The impact of S-Au bonding on SAM conductance is discussed.},
doi = {},
url = {https://www.osti.gov/biblio/926165}, journal = {Langmuir},
issn = {0743-7463},
number = 5,
volume = 24,
place = {United States},
year = {2007},
month = {11}
}