Entropy-Driven Chiral Order in a System of Achiral Bent Particles
| Autor: | Alberta Ferrarini, Cristina Greco |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Physics
Quantitative Biology::Biomolecules bent particles spontaneous chiral symmetry breaking entropy driven phase transition twist-bend nematic phase Onsager theory Molecular Dynamics simulations steric repulsion helical phase Degenerate energy levels Bent molecular geometry General Physics and Astronomy twist-bend nematic phase helical phase steric repulsion Symmetry (physics) Molecular dynamics Prochirality Liquid crystal Chemical physics Phase (matter) spontaneous chiral symmetry breaking entropy driven phase transition Excluded volume Molecular Dynamics simulations Onsager theory bent particles |
| Zdroj: | Physical review letters. 115(14) |
| ISSN: | 1079-7114 |
| Popis: | Why should achiral particles organize into a helical structure? Here, using theory and molecular dynamics simulations we show that at high concentration crescent-shaped particles interacting through a purely repulsive potential form the twist-bend nematic phase, which features helical order of the twofold symmetry axes of particles, with doubly degenerate handedness. Spontaneous breaking of the chiral symmetry is driven by the entropic gain that derives from the decrease in excluded volume in the helical arrangement. Crucial to this purpose is the concave shape of particles. This study is based on a general formulation of the Onsager theory, which includes biaxiality and polarity of phase and particles, in addition to the space modulation of order. Molecular dynamics simulations corroborate the theoretical predictions and provide further insights into the structure of the helical phase. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|