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Updated: Jun 21, 2026

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Effect of surface charge on the vibrational dynamics of interfacial water
Ali Eftekhari-Bafrooei1, Eric Borguet
1Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA.
Abstract:
The effect of the structuring of interfacial water, induced by surface charge, on the ultrafast vibrational dynamics of the O-H stretch in the hydrogen bonded spectral region was studied at the H(2)O/fused silica interface. At high pH, where the electric field resulting from deprotonation of silanol groups polarizes several layers of water molecules, fast vibrational dynamics similar to the dynamics of bulk water is observed. At the neutral surface, where the structural ordering of interfacial water and the thickness of interfacial water are smaller than those at the charged surface, the vibrational lifetime of the O-H stretch becomes more than two times longer (T(1) approximately 570 fs). The longer vibrational lifetime is a result of reduced intermolecular coupling resulting from incomplete solvation of the interfacial water species.
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