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arXiv · 1104.5670

Smectic-A and Smectic-C Phases and Phase Transitions in Liquid Crystal-Aerosil Gels

B. Freelon·M. Ramazanoglu·P. J. Chung·P. Valdivia·C. W. Garland·R. J. Birgeneau
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Abstract

High-resolution X-ray scattering studies of the nonpolar thermotropic liquid crystal 4-n-pentylphenylthiol-4'-n-octyloxybenzoate (\bar{8}S5) in aerosil gel nano-networks reveal that the aerosil-induced disorder significantly alters both the nematic to Smectic-A and Smectic-A to Smectic-C phase transitions. The limiting Smectic-A correlation length follows a power-law dependence on the aerosil density in quantitative agreement with the limiting lengths measured previously in other Smectic-A liquid crystal gels. The Smectic-A to Smectic-C liquid crystalline phase transition is altered fundamentally by the presence of the aerosil gel. The onset of the Smectic-C phase remains relatively sharp but there is an extended coexistence region where Smectic-A and Smectic-C domains can exist.

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B. Freelon, M. Ramazanoglu, P. J. Chung, P. Valdivia, C. W. Garland, R. J. Birgeneau. 2011-04-29. Smectic-A and Smectic-C Phases and Phase Transitions in Liquid Crystal-Aerosil Gels. https://doi.org/10.1103/physreve.84.031705

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