Related Experiment Video
Updated: Jun 8, 2026

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Increasing correlation length in bulk supercooled H2O, D2O, and NaCl solution determined from small angle x-ray
Congcong Huang1, T M Weiss, D Nordlund
1Stanford Synchrotron Radiation Lightsource, P.O. Box 20450, Stanford, California 94309, USA.
Water
Area of Science:
- Physical Chemistry
- Condensed Matter Physics
Background:
- Water exhibits anomalous properties, particularly in its supercooled state.
- Understanding these anomalies is crucial for various scientific disciplines.
Purpose of the Study:
- To investigate the correlation length of bulk liquid water during supercooling.
- To explore the influence of isotopic substitution (D2O) and salt (NaCl) on water's behavior.
Main Methods:
- Small-angle X-ray scattering (SAXS) was employed to measure the correlation length.
- Power law fitting was used to analyze the temperature dependence of the correlation length.
Main Results:
- A steep increase in correlation length was observed as temperature decreased in supercooled water.
- This correlation length follows a power law, suggesting fluctuations between low- and high-density regions.
- Deuterium oxide (D2O) and NaCl significantly altered the power law behavior.
Conclusions:
- Results support the hypothesis of a liquid-liquid critical point in supercooled water.
- The findings are consistent with models involving density fluctuations but do not rule out singularity-free scenarios.
More Related Videos
11:27Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2
Published on: December 8, 2016
07:19Structural Studies of Macromolecules in Solution using Small Angle X-Ray Scattering
Published on: November 5, 2018
Related Concept Videos
Determination of Crystal Structures
X-ray Crystallography
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
2D NMR: Overview of Heteronuclear Correlation Techniques
2D NMR: Overview of Homonuclear Correlation Techniques
COSY90 is the standard two-dimensional (2D) COSY experiment that...