Are critical fluctuations responsible for glass formation?

Starzonek, Szymon (author), Łoś, Joanna M. (author), Rzoska, Sylwester (author), Drozd-Rzoska, Aleksandra (author), Iglič, Aleš (author)

The dynamic heterogeneities occurring just before the transition to the glassy phase have been named as the cause of amorphization in supercooled systems. Numerous studies conducted so far have confirmed this hypothesis, and based on it, a widely accepted solution to the puzzle of glass transition has been developed. This report focuses on verifying the existence of a strong pretransitional anomaly near the glass transition ▫$T_g$▫. For this purpose, supercooled liquid-crystalline systems with a strong rod-like structure were selected. Based on the obtained experimental data, we demonstrate in this article that the previously postulated dynamic heterogeneities exhibit a critical characteristic, meaning a strong pretransitional anomaly can be observed with the described critical exponent ▫$\alpha=0.5$▫. Due to this property, it can be concluded that these heterogeneities are critical fluctuations, and consequently, the transition to the glassy state can be described based on the theory of critical phenomena. To measure the pretransitional anomaly near ▫$T_g$▫ in supercooled liquid-crystalline systems, broadband dielectric spectroscopy (BDS) and nonlinear dielectric effect (NDE) methods were applied. The exponent ▫$\alpha$▫ provides insight into the nature and intensity of critical fluctuations in the system. A value of ▫$\alpha=0.5$▫ suggests that the fluctuations become increasingly intense as the system approaches the critical point, contributing to the divergence in specific heat. Understanding the role of critical fluctuations in the glass transition is crucial for innovating and improving a wide range of materials for energy storage, materials design, biomedical applications, food preservation, and environmental sustainability. These advancements can lead to materials with superior properties, optimized manufacturing processes, and applications that meet the demands of modern technology and sustainability challenges.

• Language: English
• Keywords: glass formation, critical phenomena, phase transitions, liquid crystals, physics glass
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FE - Faculty of Electrical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 19 str.
• Numbering: Vol. 17, iss. 14, [article no.] 3385
• PID: 20.500.12556/RUL-159749
• UDC: 539.213
• ISSN on article: 1996-1944
• DOI: 10.3390/ma17143385
• COBISS.SI-ID: 202149635
• Publication date in RUL: 22.07.2024

Record is a part of a journal

• Title: Materials
• Shortened title: Materials
• Publisher: Molecular Diversity Preservation International
• ISSN: 1996-1944
• COBISS.SI-ID: 33588485

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: formacija stekla, kritični pojavi, fazni prehodi, tekoči pojavi, fizika stekla