Near-infrared spectra of H2O under high pressure and high temperature: Implications for a transition from proton tunneling to hopping states

Naoki Noguchi; Kazuki Komatsu; Ayako Shinozaki; Keiji Shinoda; Hiroyuki Kagi

doi:10.1016/j.saa.2014.06.024

Near-infrared spectra of H₂O under high pressure and high temperature: Implications for a transition from proton tunneling to hopping states

Naoki Noguchi, Kazuki Komatsu, Ayako Shinozaki, Keiji Shinoda, Hiroyuki Kagi

Research output: Contribution to journal › Article › peer-review

2 Citations (Scopus)

Abstract

The nature of protons in ice VII up to 368 °C and 16 GPa was investigated with synchrotron near-infrared spectroscopy. The absorption band of the first OH stretching overtone mode divided into doublet peaks above 5 GPa at room temperature, suggesting that proton tunneling occurs at the overtone level. As the temperature increased, the doublet peaks gradually reduced to a singlet. This result implies that thermally activated protons hop between the two potential minima along the oxygen-oxygen axis. A pressure-temperature diagram for the proton state was constructed from the changing band shape of the overtone mode.

Original language	English
Pages (from-to)	509-513
Number of pages	5
Journal	Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
Volume	133
DOIs	https://doi.org/10.1016/j.saa.2014.06.024
Publication status	Published - Dec 10 2014

Keywords

High pressure and high temperature
Ice
Near-infrared spectroscopy
Proton hopping
Proton tunneling

ASJC Scopus subject areas

Analytical Chemistry
Atomic and Molecular Physics, and Optics
Instrumentation
Spectroscopy

Access to Document

10.1016/j.saa.2014.06.024

Cite this

Near-infrared spectra of H₂O under high pressure and high temperature: Implications for a transition from proton tunneling to hopping states. / Noguchi, Naoki; Komatsu, Kazuki; Shinozaki, Ayako et al.
In: Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, Vol. 133, 10.12.2014, p. 509-513.

Research output: Contribution to journal › Article › peer-review

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