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Published on: January 26, 2016
Glass transition line in C60: a mode-coupling/molecular-dynamics study.
D Costa1, R Ruberto, F Sciortino
1Dipartimento di Fisica, Università di Messina and CNISM Ctr Papardo, 98166 Messina, Italy. dino.costa@unime.it
The Journal of Physical Chemistry. B
|August 21, 2007
Summary
Mode-coupling theory accurately predicts the C60 fullerene glass transition line, confirming a glassy phase exists within the metastable liquid-solid coexistence region.
Area of Science:
- Condensed Matter Physics
- Computational Materials Science
- Statistical Mechanics
Background:
- Understanding the glass transition is crucial for materials science.
- C60 fullerene exhibits complex phase behavior, including potential glassy states.
- Mode-coupling theory (MCT) provides a theoretical framework for studying glass transitions.
Purpose of the Study:
- To investigate the glass transition line for the Girifalco model of C60 fullerene using MCT.
- To compare theoretical predictions with results from molecular dynamics simulations.
- To determine the location and characteristics of the glassy phase in C60 fullerene.
Main Methods:
- Employed molecular dynamics simulations to obtain the equilibrium static structure factor of the C60 fullerene model.
- Utilized the structure factor as input for mode-coupling theory (MCT) calculations.
- Compared theoretical HNC and MHNC structure factors with simulation data.
Main Results:
- The MCT glass transition line was found within the metastable liquid-solid coexistence region.
- The vitrification locus extends downwards in temperature and terminates on the liquid side of the liquid-vapor binodal.
- Theoretical MCT predictions closely matched the shape of the simulated glass line and structure factors.
Conclusions:
- Mode-coupling theory accurately reproduces the glass transition line for the C60 fullerene model.
- The study confirms the existence of a glassy phase for this fullerene model.
- Results validate the use of MCT for predicting glass behavior in complex molecular systems.
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