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Published on: September 17, 2021
Viscoelasticity and metastability limit in supercooled liquids
Andrea Cavagna1, Alessandro Attanasi, José Lorenzana
1Centre for Statistical Mechanics and Complexity, INFM, Via dei Taurini 19, 00185 Roma, Italy.
Physical Review Letters
|October 4, 2005
Summary
Elastic effects in supercooled liquids significantly influence the kinetic spinodal, a temperature below which crystal nucleation time exceeds relaxation time. A new parameter, lambda, determines if this metastability limit is suppressed or present, impacting experimental observation times.
Area of Science:
- Materials Science
- Physical Chemistry
- Condensed Matter Physics
Background:
- Supercooled liquids exhibit unique properties below their freezing point.
- Classical nucleation theory describes crystal formation but often neglects liquid viscoelasticity.
- The kinetic spinodal marks a temperature threshold related to liquid relaxation and crystal nucleation times.
Purpose of the Study:
- To investigate the influence of liquid viscoelasticity on classical nucleation theory.
- To determine the impact of elastic effects on the kinetic spinodal.
- To introduce and analyze a new dimensionless parameter governing liquid metastability.
Main Methods:
- Revisiting classical nucleation theory with viscoelastic considerations.
- Introducing a dimensionless parameter lambda (ratio of infinite frequency shear modulus to crystal enthalpy of fusion).
- Analyzing the dependence of the kinetic spinodal on lambda and surface tension.
Main Results:
- Elastic effects strongly influence the kinetic spinodal.
- A critical value lambda(c) determines the presence or absence of the kinetic spinodal.
- If lambda > lambda(c), the metastability limit is suppressed regardless of surface tension.
- If lambda < lambda(c), a kinetic spinodal exists, with observable time scaling exponentially with lambda and surface tension effects.
Conclusions:
- The viscoelastic response of supercooled liquids is crucial for understanding nucleation phenomena.
- The parameter lambda provides a new metric for predicting liquid metastability.
- Elastic properties can fundamentally alter or eliminate the kinetic spinodal, impacting crystallization behavior.
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