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arXiv · 2504.02954

Surface charge pattern: impact on vibrational spectroscopy and physics of charged interfaces

Wanlin Chen·Marie-Pierre Gaigeot·Simone Pezzotti
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Abstract

Surface specific vibrational spectroscopies revolutionized the study of charged interfaces, by sensitively probing water's response in the electric double layer (EDL) and correlating it with surface charge via models like Gouy Chapmann Stern. The assumed one to one relationship between water's spectroscopic response and surface charge has been widely accepted without question. We hereby propose a theoretical experiment to evaluate this assumption. Interestingly, our findings reveal a non one to one relationship between surface charge and spectroscopic response, exhibiting a fascinating dependence on surface topology.

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Wanlin Chen, Marie-Pierre Gaigeot, Simone Pezzotti. 2025-04-03. Surface charge pattern: impact on vibrational spectroscopy and physics of charged interfaces. https://arxiv.org/abs/2504.02954

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