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arXiv · 0909.2625

Stable smectic phase in suspensions of polydisperse colloidal platelets with identical thickness

Dazhi Sun·Hung-Jue Sue·Zhengdong Cheng·Yuri Martinez-Raton·Enrique Velasco
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Abstract

We report the nematic and smectic ordering in a new aqueous suspension of monolayer $\alpha$-Zirconium phosphate platelets possessing a high polydispersity in diameter but uniform thickness. We observe an isotropic--nematic transition as the platelet volume fraction increases, followed by the formation of a smectic, an elusive phase that has been rarely seen in discotic liquid crystals. The smectic phase is characterized by X-ray diffraction, high-resolution transmission electron microscopy, and optical microscopy. The phase equilibria in this highly polydisperse suspension is rationalized in terms of a theoretical approach based on density--functional theory.

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Dazhi Sun, Hung-Jue Sue, Zhengdong Cheng, Yuri Martinez-Raton, Enrique Velasco. 2009-09-14. Stable smectic phase in suspensions of polydisperse colloidal platelets with identical thickness. https://doi.org/10.1103/physreve.80.041704

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