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Updated: Aug 8, 2026

Neutron Crystallography Data Collection and Processing for Modelling Hydrogen Atoms in Protein Structures
Published on: December 1, 2020
The local structure of protonated water from x-ray absorption and density functional theory
Matteo Cavalleri1, Lars-Ake Näslund, David C Edwards
1Fysikum, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden.
Abstract:
We present a combined x-ray absorption spectroscopy/computational study of water in hydrochloric acid (HCl) solutions of varying concentration to address the structure and bonding of excess protons and their effect on the hydrogen bonding network in liquid water. Intensity variations and energy shifts indicate changes in the hydrogen bonding structure in water as well as the local structure of the protonated complex as a function of the concentration of protons. In particular, in highly acidic solutions we find a dominance of the Eigen form, H(3)O(+), while the proton is less localized to a specific water under less acidic conditions.
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