Simulation-Comparative Approach to Description of Glass Structural Relaxation Dynamics

Abstract

Accurate description of structural relaxation processes is essential for predicting long-term stability of chalcogenide glasses utilized in memory, photonic, and infrared-optical applications. Although the Tool–Narayanaswamy–Moynihan (TNM) model remains one of the most effective frameworks for describing the glass transition kinetics, determination of its nonlinearity (x) and nonexponentiality (β) related features is often hindered by instrumental distortions and instability of the conventional curve-fitting procedures. Here, a robust and user-friendly implementation of the simulation-comparative method for extraction of the x and β TNM parameters is presented. An extensive library of precomputed core data sets is introduced, covering physically relevant ranges of enthalpy relaxation activation energy (200–500 kJ·mol–1) and glass transition temperatures (−50–450 °C) for chalcogenide glasses. Utilization of these data sets in terms of the presented simulation-comparative method enables rapid, fitting-free estimation of x and β by direct comparison with experimental calorimetric data, using only basic data-processing tools. The predictive performance of the method was systematically validated─using defined and randomly generated theoretically simulated data sets, as well as experimental calorimetric data extracted from the literature─the method predicts the parameters x and β with an uncertainty of ±0.05, further decreasing this uncertainty to ±0.02 for the most relevant cases of the relaxation behavior. By eliminating the need for specialized software and unstable optimization routines, the presented approach substantially lowers the barrier for routine TNM analysis and enables reliable monitoring of subtle structural relaxation trends in chalcogenide glasses. The provided core data sets, together with accompanying MATLAB code, establish a practical and broadly applicable platform for structural relaxation studies in amorphous chalcogenide materials.