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08:44
Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene
Published on: August 22, 2017
Glass transition in fullerenes: mode-coupling theory predictions
1SUPA, School of Physics, The University of Edinburgh, JCMB, The King's Buildings, Edinburgh EH9 3JZ, United Kingdom. m.j.greenall@leeds.ac.uk
The Journal of Chemical Physics
|November 30, 2006
Summary
Mode-coupling theory reveals fullerene glass transitions are driven by attraction, not just repulsion. This kinetic arrest occurs at lower densities than typical liquids, with attraction
Area of Science:
- Condensed matter physics
- Theoretical chemistry
- Materials science
Background:
- Fullerenes exhibit complex phase behavior.
- Understanding glass transitions is crucial for materials science.
- Kinetic arrest in molecular systems is often dominated by excluded-volume effects.
Purpose of the Study:
- Investigate the glass transition of model fullerene systems.
- Determine the role of interparticle attraction versus repulsion.
- Map transition lines in the temperature-density phase space.
Main Methods:
- Idealized mode-coupling theory (MCT) was employed.
- Phenomenological two-body potentials were used for interactions.
- Simulations considered C60, C70, and C96 fullerene models.
Main Results:
- Transition lines for fullerene glass formation were identified.
- Kinetic arrest is significantly influenced by interparticle attraction.
- Arrest occurs at lower densities compared to hard-sphere or Lennard-Jones systems.
Conclusions:
- Fullerene glass transitions deviate from standard liquid behavior due to strong attractive forces.
- The impact of attraction intensifies with increasing fullerene size.
- Achieving colloid-like glass-glass transitions requires unrealistically large fullerenes.
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