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Updated: Apr 28, 2026

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Tunneling spectroscopy measurements on hydrogen-bonded supramolecular polymers
François Vonau1, Roozbeh Shokri, Dominique Aubel
1Institut des Sciences de Matériaux de Mulhouse, CNRS-UMR 7361, Université de Haute Alsace, 3B, rue Alfred Werner, 68093 Mulhouse, France. Laurent.Simon@uha.fr.
Abstract:
We studied the formation of hydrogen-bonded supramolecular polymers of Ethyl Hexyl Urea Toluene (EHUT) on a gold (111) surface by low temperature scanning tunneling microscopy. Tunneling spectroscopy performed along an individual molecule embedded in a self-assembled layer revealed strong changes in the value of the HOMO-LUMO gap. A variation of the LUMO state is attributed to the effect of space charge accumulation resulting from anisotropic adhesion of the molecule. In addition, for specific tunneling conditions, changes induced through the formation of hydrogen bonds became visible in the differential conductance (dI/dV) maps; isolated molecules, hydrogen bonded dimers and supramolecular polymers of EHUT were distinguishable through their electronic properties.
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