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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
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Phase behavior of hard cylinders
Joyce T Lopes1, Flavio Romano2, Eric Grelet3
1Universidade Estadual de Campinas, Faculdade de Engenharia Química, Departamento de Engenharia de Sistemas Químicos, Campinas, Brazil.
The Journal of Chemical Physics
|March 16, 2021
Summary
This study maps the phase diagram for hard cylindrical particles. For prolate cylinders (L/D > 1), nematic and smectic phases emerge. For oblate cylinders (L/D < 1), cubatic, nematic, and columnar phases are stable.
Area of Science:
- Physics
- Materials Science
- Computational Chemistry
Background:
- Understanding the phase behavior of anisotropic particles is crucial for materials science.
- Cylindrical particles exhibit complex phase diagrams influenced by their aspect ratio.
- Previous studies on hard cylinders have provided partial phase diagrams, necessitating a comprehensive investigation.
Purpose of the Study:
- To computationally map the complete phase diagram of hard cylindrical particles.
- To investigate the influence of particle aspect ratio (L/D) on phase behavior.
- To identify stable and metastable phases and their transition points.
Main Methods:
- Isobaric Monte Carlo simulations were employed.
- An improved algorithm for detecting cylinder overlap was utilized.
- Simulations covered both prolate (L/D > 1) and oblate (L/D < 1) geometries.
Main Results:
- For prolate cylinders, isotropic (I), nematic (N), smectic (SmA), and crystal (X) phases were identified, with I-N-SmA and I-SmA-X triple points.
- A metastable columnar (C) phase was observed for prolate cylinders.
- For oblate cylinders, stable intermediate phases included cubatic (Cub), nematic (N), and columnar (C), with triple points I-N-Cub, N-Cub-C, and I-Cub-C.
Conclusions:
- The study provides a comprehensive phase diagram for hard cylindrical particles, revealing distinct behaviors for prolate and oblate shapes.
- The findings highlight the stability of cubatic, nematic, and columnar phases in oblate systems.
- This work offers a foundation for more complex models with potential applications in biological systems like viruses and nucleosomes.
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