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Entropy driven formation of a chiral liquid crystalline phase of helical filaments

Edward Barry·Zach Hensel·Michael Shribak·Rudolf Oldenbourg·Zvonimir Dogic
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Abstract

We study the liquid crystalline phase behavior of a concentrated suspension of helical flagella isolated from {\it Salmonella typhimurium}. Flagella are prepared with different polymorphic states, some of which have a pronounced helical character while others assume a rod-like shape. We show that the static phase behavior and dynamics of chiral helices are very different when compared to simpler achiral hard rods. With increasing concentration, helical flagella undergo an entropy driven first order phase transition to a liquid crystalline state having a novel chiral symmetry.

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Edward Barry, Zach Hensel, Michael Shribak, Rudolf Oldenbourg, Zvonimir Dogic. 2005-10-26. Entropy driven formation of a chiral liquid crystalline phase of helical filaments. https://doi.org/10.1103/physrevlett.96.018305

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