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Updated: Aug 23, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Changes in the structure of water deduced from the pressure dependence of the Raman OH frequency
Tatsuhiko Kawamoto1, Shukichi Ochiai, Hiroyuki Kagi
1Institute for Geothermal Sciences, Graduate School of Science, Kyoto University, Beppu 874-0903, Japan. kawamoto@bep.vgs.kyoto-u.ac.jp
Abstract:
We report on the Raman spectra of water under high temperature and pressure conditions and show a discontinuity in the pressure dependence of the OH stretching frequency. As pressure increases, the strength of hydrogen bonding increases rapidly in the pressure ranges up to 0.4+/-0.1 GPa at 25 degrees C, 1.0+/-0.1 GPa at 100 degrees C, and 1.3+/-0.1 GPa at 300 degrees C and slowly above these pressures. This finding clearly demonstrates the existence of discontinuities in the pressure response of the hydrogen bonds of water, which suggests a possible structural change under these conditions.
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