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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Relation between the Widom line and the dynamic crossover in systems with a liquid-liquid phase transition
Limei Xu1, Pradeep Kumar, S V Buldyrev
1Center for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215, USA.
Summary
Researchers found a link between dynamic changes and thermodynamic anomalies in liquids with a liquid-liquid critical point. This connection, observed in water and other models, helps explain liquid behavior near critical points.
Area of Science:
- Physical Chemistry
- Computational Fluid Dynamics
- Materials Science
Background:
- Liquids can exhibit anomalies near a liquid-liquid critical point (LLCP).
- Understanding the relationship between dynamic and thermodynamic anomalies is crucial for fluid behavior studies.
- Water's unique properties are often linked to its hydrogen-bonding network and potential LLCP.
Purpose of the Study:
- To investigate the correlation between dynamic anomalies and thermodynamic anomalies in liquids with an LLCP.
- To explore the universality of the connection between dynamic crossover and the Widom line.
- To examine this relationship in both water models and a generic Jagla potential.
Main Methods:
- Molecular dynamics simulations were used to study two water models and the Jagla potential.
- Analysis focused on identifying dynamic crossovers and thermodynamic anomalies, specifically specific heat maxima (Widom line).
- Comparison of simulation results with experimental data from neutron scattering on confined water.
Main Results:
- A clear correlation was found between dynamic crossover phenomena and the Widom line (locus of C(P)(max)) in both water models.
- The findings support a link between the hypothesized liquid-liquid phase transition and observed dynamic transitions in confined water.
- The Jagla potential, a generic model, also exhibits this connection, suggesting a broader applicability beyond water.
Conclusions:
- The study demonstrates a general connection between specific heat maxima (Widom line) and dynamic crossover in liquids with LLCPs.
- This finding provides a framework for understanding dynamic anomalies in various liquids, not just water.
- The results contribute to the fundamental understanding of phase transitions and anomalous behavior in liquids.
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