2025/09/11 by Ryzhov, Alexander, Kapralov, Pavel, Stolov, Mikhail +4
#Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Soft Condensed Matter (cond-mat.soft)
paper · doi:10.48550/arxiv.2509.09462
We report cross-validated measurements of the isotope effect on dielectric relaxation for four isotopologues of ice and water, including the 1-105 Hz region, in which only sporadic and inconsistent measurements were previously available. In ice, the relaxation rates exhibit an activated temperature dependence with an isotope-independent activation energy. Across 248-273 K, the H2O/D2O relaxation rate ratio remains constant at 2.0 ± 0.1. This scaling agrees with Kramers' theory in the high-friction limit if the moving mass is the proton or deuteron, indicating that dielectric relaxation is governed by a classic proton transfer over an energy barrier rather than molecular reorientation.