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arXiv · 2106.08633

Large heat-capacity jump in cooling-heating of fragile glass from kinetic Monte Carlo simulations based on a two-state picture

Chun-Shing Lee·Hai-Yao Deng·Cho-Tung Yip·Chi-Hang Lam
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Abstract

The specific heat capacity $c_v$ of glass formers undergoes a hysteresis when subjected to a cooling-heating cycle, with a larger $c_v$ and a more pronounced hysteresis for fragile glasses than for strong ones. Here, we show that these experimental features, including the unusually large magnitude of $c_v$ of fragile glasses, are well reproduced by kinetic Monte Carlo and equilibrium study of a distinguishable particle lattice model (DPLM) incorporating a two-state picture of particle interactions. The large $c_v$ in fragile glasses is caused by a dramatic transfer of probabilistic weight from high-energy particle interactions to low-energy ones as temperature decreases.

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Chun-Shing Lee, Hai-Yao Deng, Cho-Tung Yip, Chi-Hang Lam. 2021-06-16. Large heat-capacity jump in cooling-heating of fragile glass from kinetic Monte Carlo simulations based on a two-state picture. https://doi.org/10.1103/physreve.104.024131

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