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Updated: Jul 28, 2026
10:03
The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
Hydrogen bonds in liquid water are broken only fleetingly
J D Eaves1, J J Loparo, C J Fecko
1Department of Chemistry and George R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Summary
Liquid water
Area of Science:
- Physical Chemistry
- Chemical Physics
- Spectroscopy
Background:
- Liquid water exhibits local tetrahedral structures stabilized by hydrogen bonds.
- The mechanism of hydrogen bond switching between water molecules is not fully understood.
- Nonhydrogen-bonded configurations (NHBs) play a crucial role in hydrogen bond dynamics.
Purpose of the Study:
- To investigate the stability and dynamics of nonhydrogen-bonded configurations (NHBs) in liquid water.
- To elucidate the role of NHBs in the hydrogen bond switching mechanism.
- To differentiate between NHB as a transition state versus a transient species.
Main Methods:
- Femtosecond 2D infrared (2D IR) spectroscopy was employed.
- Molecular dynamics (MD) simulations were performed.
- An isotopically dilute mixture (HOD in D2O) was studied to isolate OH vibrational signals.
Main Results:
- 2D IR spectra indicated distinct relaxation dynamics for hydrogen-bonded and NHB configurations.
- NHBs relax to hydrogen-bonded frequencies on the timescale of water's fastest intermolecular motions.
- MD simulations reproduced experimental 2D IR spectra and showed NHBs are intrinsically unstable, returning to hydrogen bonding within 200 fs.
Conclusions:
- Nonhydrogen-bonded configurations (NHBs) in liquid water are intrinsically unstable.
- Dangling hydrogen bonds are an insignificant species in liquid water.
- NHBs represent transient states within the hydrogen-bonded well, not stable intermediates.
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