Thermodynamic Evidence for Water as a Quantum Mechanical Liquid

2010/01/22 by A. Widom, Widom, A., J. E. Swain +7
Earth and Planetary Sciences · Physics and Astronomy · #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #High-pressure geophysics and materials #Other Condensed Matter (cond-mat.other) #Quantum Physics (quant-ph) #Quantum, superfluid, helium dynamics

paper · pdf · doi:10.48550/arxiv.1001.4090

openalex publication_date 2010/01/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We consider general theoretical models of water and in particular the nature of the motions of the hydrogen nuclei. If the motion of hydrogen nuclei is classical, then the thermodynamic pressure equation of state for heavy water wherein the hydrogen nuclei are deuterons is identical to the pressure equation of state for light water wherein the hydrogen nuclei are protons. Since the experimental thermodynamic phase diagram for light water is clearly measurably different from the experimental thermodynamic phase diagram for heavy water, one may deduce that the motions of hydrogen nuclei are quantum mechanical in nature. This conclusion is in physical agreement with a recent analysis of X-ray, neutron and deep inelastic neutron scattering data.

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