Electric-field control of hydrogen bonding via interfacial charge at atomic resolution

TL;DR

This study demonstrates how an external electric field can reversibly control hydrogen-bond networks in monolayer ice on graphite by inducing interfacial charge redistribution, enabling precise manipulation of molecular organization at atomic scale.

Contribution

It reveals a novel mechanism where electric fields modulate hydrogen-bond networks through interfacial charge redistribution, supported by experimental and theoretical evidence.

Findings

Electric field induces reversible transition from non-wetting water to ordered monolayer.

Systematic field variation causes coupled structural and electronic responses.

Field reversal enables switching between equivalent dipolar configurations.

Abstract

Hydrogen-bond networks govern molecular structure and function across chemistry, biology and materials science, yet their deterministic control at the atomic scale remains a central challenge (1-9).Here, we directly visualize how an external electric field enables reversible control of a hydrogen-bond network in monolayer ice on graphite through interfacial charge redistribution. Low-temperature scanning tunnelling microscopy reveals a field-driven transition from a mobile, physisorbed, non-wetting water phase to an ordered hexagonal monolayer, enabling deterministic nucleation, growth and complete wetting on an otherwise inert surface. Systematic variation of the field induces continuous lattice strain coexisting with discrete conductance states, revealing coupled structural and electronic responses. Reversal of the field polarity drives collective dipolar inversion, enabling switching between symmetry-equivalent configurations without disrupting the lattice. Supported by first-principles theory and bias-dependent imaging, these effects arise from field-induced modification of the interfacial electronic structure rather than purely geometric or orientational effects. These results establish interfacial charge redistribution as a general mechanism for electrically programming hydrogen-bond networks, providing a route to control molecular organization, electronic properties and collective dipolar order at interfaces.