Fragility by elastic incoherent neutron scattering.
S Magazù1, G Maisano, F Migliardo
1Dipartimento di Fisica and INFM, Università di Messina, P.O. Box 55, I-98166 Messina, Italy. smagazu@unime.it
The Journal of Chemical Physics
|November 6, 2004
Summary
This study defines material fragility using elastic incoherent neutron scattering (EINS). The findings reveal a direct linear relationship between EINS-derived fragility (M) and viscosity-based fragility (m) in glass-forming systems.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Material fragility is a key property influencing the behavior of glass-forming systems.
- Understanding the relationship between macroscopic properties (viscosity) and nanoscopic behavior (atomic motion) is crucial.
Purpose of the Study:
- To establish an operational definition for the fragility degree using elastic incoherent neutron scattering (EINS).
- To correlate fragility measurements obtained via EINS with those derived from viscosity.
Main Methods:
- Utilized elastic incoherent neutron scattering (EINS) to probe atomic dynamics.
- Measured viscosity of glass-forming systems.
- Analyzed the relationship between atomic mean-square displacement and viscosity.
Main Results:
- An operative definition for fragility degree was established using EINS.
- A linear dependence was observed between the fragility parameter M (from EINS) and the fragility parameter m (from viscosity).
Conclusions:
- EINS provides a valid method for quantifying material fragility.
- The established link between EINS and viscosity offers a new perspective on understanding glass-forming dynamics.
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