Work

Testing the validity of Adam–Gibbs equation

Year: 2025

Type: article

Abstract: The Adam–Gibbs (AG) equation may be one of the most influential models in the study of α-relaxation. In this paper, we derived mathematical relationships governing changes in the potential barrier and configurational entropy from a series of nonlinearly scaled potential energy landscapes. By integrating these relationships with molecular dynamics simulations, we revisited the renowned AG model, which establishes a direct correlation between the α-relaxation time, configurational entropy, and potential barrier. Our findings confirm that the AG model effectively depicts the temperature dependence of the α-relaxation time. Additionally, we reassessed other widely used models for α-relaxation, including the Vogel–Fulcher–Tammann model, the shoving model, the Mauro–Yue–Ellison–Gupta–Allan model, and various quadratic-form models, to evaluate their applicability under varying potential barriers. Our results indicate that the potential barrier plays a critical role in these relaxation models. These models perform well when the average potential barrier is high. However, discrepancies arise when the average potential barrier decreases. This research provides an in-depth analysis of α-relaxation, offering new insights into the dynamics of supercooled liquids.

Source: Journal of Applied Physics

DOI: 10.1063/5.0243030

Authors: B. Zhang, D. M. Zhang, D. Y. Sun, X. G. Gong

Institutions: East China Normal University, Fudan University

Language: English

Topic: Material Dynamics and Properties

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,500

Funders: National Natural Science Foundation of China, National Key Research and Development Program of China