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Updated: May 17, 2026

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Solvation Structure and Energetics of Single Ions at the Aqueous Liquid-Vapor Interface
Brad A Bauer1, Shuching Ou, Sandeep Patel
1Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Abstract:
Potentials of mean force for single, nonpolarizable monovalent halide anions and alkali cations are computed for transversing the water-air interface (modeling using polarizable TIP4P-FQ and TIP4P-QDP). Iodide and bromide in TIP4P-FQ show interfacial stability, whereas chloride, bromide, and iodide show interfacial stability in TIP4P-QDP. A monotonic decrease in coordination number and an increasingly anisotropic distribution of solvating water molecules is shown to accompany movement of the ions towards vapor conditions; these effects are most noticeable with increases in ion size/decreases in magnitude of hydration free energy.
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