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arXiv · 2405.05612

Prigogine-Defay ratio of glassy freezing scales with liquid fragility

Alois Loidl·Peter Lunkenheimer·Konrad Samwer
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Abstract

A detailed study of published experimental data for a variety of materials on the incremental variation of heat capacity, thermal expansion, and compressibility at glassy freezing reveals a striking dependence of the Prigogine-Defay ratio R on the fragility index m. At high m, R approaches values of ~1, the Ehrenfest expectation for 2nd order continuous phase transitions, while R reaches values > 20 for low fragilities. We explain this correlation by the degree of separation of the glassy freezing temperature from a hidden phase transition into an ideal low-temperature glass.

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Alois Loidl, Peter Lunkenheimer, Konrad Samwer. 2024-05-09. Prigogine-Defay ratio of glassy freezing scales with liquid fragility. https://doi.org/10.1103/physreve.111.035407

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