Supercooled liquids display sluggish dynamics, often attributed to their structural characteristics, yet the underlying mechanism remains elusive. Here we conduct numerical investigations into the structure-dynamics relationship in model glass-forming liquids, with a specific focus on an elementary particle rearrangement mode known as the 'T1 process'. We discover that the ability of a T1 process to preserve glassy structural order before and after is pivotal towards determining a liquid's fragility-whether it exhibits super-Arrhenius-like or Arrhenius-like behaviour. If a T1 process disrupts local structural order, it must occur independently without cooperativity, resulting in Arrhenius-like behaviour. By contrast, if it can maintain order, it sequentially propagates from disordered peripheries to the middle of high-structural-order regions, leading to cooperativity and super-Arrhenius-like behaviour. Our study establishes a microscopic link between liquid-structure ordering, dynamic cooperativity and super-Arrhenius-like dynamics, extending the understanding of the structure-dynamics relationships in supercooled liquids.
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http://dx.doi.org/10.1038/s41563-024-02068-8 | DOI Listing |
Nat Mater
January 2025
Department of Fundamental Engineering, Institute of Industrial Science, The University of Tokyo, Tokyo, Japan.
Supercooled liquids display sluggish dynamics, often attributed to their structural characteristics, yet the underlying mechanism remains elusive. Here we conduct numerical investigations into the structure-dynamics relationship in model glass-forming liquids, with a specific focus on an elementary particle rearrangement mode known as the 'T1 process'. We discover that the ability of a T1 process to preserve glassy structural order before and after is pivotal towards determining a liquid's fragility-whether it exhibits super-Arrhenius-like or Arrhenius-like behaviour.
View Article and Find Full Text PDFAdv Mater
January 2025
State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, School of Physics and Optoelectronics, South China University of Technology, Guangzhou, 510641, China.
J Phys Chem B
January 2025
CAS Key Laboratory of Magnetic Materials and Devices, and Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
The glacial phase can be formed from supercooled liquid (SCL) in certain systems, which is called liquid-liquid transition (LLT). Revealing the nature of the glacial phase especially in a single-component system is crucial for understanding the LLT process. Here, by using flash differential scanning calorimetry and cold-field transmission electron microscopy, the structure of the d-mannitol glacial phase and the phase transition kinetics between the glacial phase and SCL were studied.
View Article and Find Full Text PDFInorg Chem
December 2024
Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, U.K.
ABX-type hybrid organic-inorganic structures have recently emerged as a new class of meltable materials. Here, by the use of phenylphosphonium derivatives as A cation, we study liquid- and glass-forming behavior of a new family of hybrid structures, (RPhP)[Mn(dca)] (R = Me, Et, Ph; dca = dicyanamide). These new compounds melt at 196-237 °C () and then vitrify upon cooling to room temperature, forming glasses.
View Article and Find Full Text PDFJ Phys Chem B
December 2024
August Chełkowski Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland.
The fundamental Debye-Stokes-Einstein (DSE) relation between rotational relaxation times and shear viscosity attracts longstanding research interest as one of the most important characteristics of many glass-forming liquids. Here, we provide strong evidence, missing so far, for the relevance of anisotropy for DSE-related behavior. Dielectric spectroscopy and shear viscosity measurements were employed to get insight into the decoupling between reorientation relaxation times and viscosity for anisotropic glass-formers with dipole moments oriented parallel or perpendicular to the long molecular axis.
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