Thermodynamic character of glass transition is possible!

In the latest paper entitled „New paradigm for configurational entropy in glass-forming systems” Colleagues from the X-PressMatter Laboratory (NL10, Aleksandra Drozd-Rzoska, Sylwester J. Rzoska, Szymon Starzonek) published in Scientific Reports (Nature-Springer) [https: // www. nature.com/articles/s41598-022-05897-2] showed that the current definition of the configuration entropy for the transition to the glass state is far inadequate. It turned out that using the developed methodology of the Physics of Critical Phenomena, it is possible to precisely determine the Kauzmann temperature and describe the changes in the configuration entropy in the wide glass transition temperature environment using a critical-like function with an exponent n, which assumes identical values for both the specific heat and the configuration entropy (thermodynamics) and dielectric relaxation (dynamics). What is especially worth emphasizing – its value correlates with the local molecular symmetry. The generalized (critical-like) relationship for entropy leads to the „generalized” Vogel-Fulcher-Tammann equation (VFT) for the description of viscosity, relaxation time, diffusion, electrical and thermal conductivity. It also leads to breakthrough consequences for concepts as fundamental in vitrification as brittleness or activation enthalpy. The glass transition is usually indicated as a dynamic phenomenon, which heuristically justifies by far-reaching pre-vitrification changes in the structural relaxation time or a similar evolution for viscosity. This is also confirmed by the dependence of the glass transition temperature on the cooling rate. In the aforementioned work, it was unequivocally demonstrated that the changes in the configuration entropy are described by a power function with a universal exponent depending on symmetry. Is this not like a critical phenomenon? Is this not a proof, that Kauzmann temperature is a specific critical temperature? So, are we not on the way to the Great Unification of critical and pre-vitrification phenomena?

(left) Dependence of configuration entropy on temperature for selected substances. Fit with a classical function (red, n = 1) and a critical-like function (blue, n ≠ 1). (right) Pre-nitrification dependence of specific configuration heat for selected substances. The inset shows the pre-transient effect of specific heat around the glass transition temperature Tg.

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