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Updated: Aug 6, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Geometrically driven reversible solid-liquid phase transition at the atomic scale
Wenjun Cui1,2,3,4, Cheng Qian5, Weixiao Lin1,3
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, China.
Science (New York, N.Y.)
|July 16, 2026
Summary
Geometric confinement dictates phase transitions in bismuth nanoclusters. Aspect ratio, not volume, governs liquid-solid transformations, enabling tailored nanomaterial design through controlled nucleation.
Area of Science:
- Materials Science
- Nanotechnology
- Physical Chemistry
Background:
- Understanding heterogeneous nucleation is crucial for controlling nanomaterial properties.
- Geometrically confined systems offer unique platforms for studying fundamental phase transitions.
- Previous studies have explored confinement effects, but atomic-resolution insights into nucleation mechanisms remain limited.
Purpose of the Study:
- To investigate the atomic-resolution liquid-solid phase transition in geometrically confined nanoclusters.
- To elucidate the role of confinement and aspect ratio in heterogeneous nucleation.
- To establish a mechanistic foundation for geometry-driven phase and orientation selection in nanomaterials.
Main Methods:
- In situ transmission electron microscopy (TEM) was employed to observe a single bismuth nanocluster.
- A tunable nanoscale gap was utilized to control and confine the nanocluster.
- The nanocluster was driven through a reversible phase transition cycle (quasi-amorphous, crystalline, liquid).
Main Results:
- The aspect ratio, not volume, was identified as the primary factor governing phase transitions.
- Confinement imposed a preferred crystallographic orientation ([Formula: see text]) in the crystalline nanowire phase.
- The interplay between surface anisotropy and interfacial energetics dictates the observed phase behaviors.
Conclusions:
- Engineered confinement provides a powerful tool for controlling phase transitions and material texture at the nanoscale.
- The findings offer fundamental insights into heterogeneous nucleation mechanisms.
- This work enables the rational design of nanomaterials by leveraging geometric confinement for phase and orientation selection.
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