Deciphering the infrared spectrum of the hydrated proton using full-dimensional quantum dynamics

Nature Chemistry, Published online: 27 July 2026; doi:10.1038/s41557-026-02209-3 The infrared spectra of the aqueous proton show dynamic character beyond the classical Zundel H+(H2O)2 and Eigen H+(H2O)3 structural motifs. Fully quantum modelling the larger H+(H2O)6 complex provides a direct link between asymmetric solvation environments and the spectroscopic response of the solvated proton.