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Updated: Aug 1, 2026
10:28
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Dynamics and unsteady morphologies at ice interfaces driven by D2O-H2O exchange.
Ran Drori1,2,3, Miranda Holmes-Cerfon4, Bart Kahr5,2
1Department of Chemistry, New York University, New York, NY 10003; mdw3@nyu.edu rdrori@yu.edu holmes@cims.nyu.edu.
Summary
Investigating heavy water (D2O) ice growth in light water (H2O) revealed complex dynamics. H2O diffusion into D2O ice causes melting, while cooling drives growth, leading to interface instability and unique scalloped patterns near 0°C.
Area of Science:
- Physical Chemistry
- Materials Science
- Fluid Dynamics
Background:
- Understanding phase transitions of water isotopes is crucial for various scientific fields.
- Investigating ice growth dynamics in confined microfluidic environments presents unique challenges and opportunities.
- The interplay between diffusion, thermal gradients, and interface phenomena governs crystal growth.
Purpose of the Study:
- To investigate the growth dynamics of heavy water (D2O) ice in liquid light water (H2O) within a microfluidic device.
- To elucidate the mechanisms controlling ice front advancement and retreat under varying cooling rates and temperatures.
- To characterize the role of hydrogen-deuterium (H/D) exchange and interface morphology during D2O ice growth.
Main Methods:
- Utilized a microfluidic device to control and observe ice growth.
- Employed controlled cooling rates ranging from 0.002 °C/s to 0.1 °C/s.
- Applied Raman microscopy to track H/D exchange across the solid-liquid interface.
Main Results:
- D2O ice front advanced during cooling but retreated upon cessation, driven by H2O diffusion and cooling forces.
- Raman microscopy confirmed H/D exchange, indicating intact H2O molecule transport at the D2O ice interface.
- A scalloped interface morphology with cycling growth and retreat emerged near 0°C, distinct from pure H2O or D2O systems.
Conclusions:
- The observed D2O ice growth dynamics result from a competition between H2O diffusion-driven melting and cooling-induced growth.
- H/D exchange, thermal gradients, and Gibbs-Thomson effects contribute to the complex, non-monotonic interface behavior.
- The unique scalloped morphology highlights cooperative phenomena not seen in simpler ice-water systems.
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