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arXiv · 0707.2091

Amine-Gold Linked Single-Molecule Junctions: Experiment and Theory

Su Ying Quek·Latha Venkataraman·Hyoung Joon Choi·Steven G. Louie·Mark S. Hybertsen·J. B. Neaton
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Abstract

The measured conductance distribution for single molecule benzenediamine-gold junctions, based on 59,000 individual conductance traces recorded while breaking a gold point contact in solution, has a clear peak at 0.0064 G$_{0}$ with a width of $\pm$ 40%. Conductance calculations based on density functional theory (DFT) for 15 distinct junction geometries show a similar spread. Differences in local structure have a limited influence on conductance because the amine-Au bonding motif is well-defined and flexible. The average calculated conductance (0.046 G$_{0}$) is seven times larger than experiment, suggesting the importance of many-electron corrections beyond DFT.

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Su Ying Quek, Latha Venkataraman, Hyoung Joon Choi, Steven G. Louie, Mark S. Hybertsen, J. B. Neaton. 2007-07-16. Amine-Gold Linked Single-Molecule Junctions: Experiment and Theory. https://doi.org/10.1021/nl072058i

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