J. Phys. II France
Volume 4, Numéro 6, June 1994
Page(s) 975 - 988
DOI: 10.1051/jp2:1994178
J. Phys. II France 4 (1994) 975-988

Spherulite phase induction from positive Gaussian curvature in lyotropic lamellar liquid crystals

J. B. Fournier and G. Durand

Laboratoire de Physique des Solides, Université Paris-Sud, bât. 510, 91405 Orsay, France

(Received 23 November 1993, revised 31 January 1994, accepted 3 March 1994)

The equilibrium properties of spherulite assemblies in lyotropic lamellar phases are studied within both elastic and statistical models. Following previous models, the spherulites are assumed to be stabilized by their positive Gaussian curvature. Our model predicts that the spherulites should adopt a regular crystalline piling if their core energy $E_{\rm c}$ is much larger than $k_{\rm B} T$, or a liquid-like piling with large radius fluctuations if $E_{\rm c} \sim k_{\rm B} T$. The spherulites develop an internal pressure depending only on temperature. The existence of a maximum in the distribution of spherulite radii gives a practical criterion for checking the Gaussian curvature efficiency.

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