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Hydrogen-bonded Silica Gels Dispersed in a Smectic Liquid Crystal: A Random Field XY System

S. Park·R. L. Leheny·R. J. Birgeneau·J. -L. Gallani·C. W. Garland·G. S. Iannacchione
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Abstract

The effect on the nematic to smectic-A transition in octylcyanobiphenyl (8CB) due to dispersions of hydrogen-bonded silica (aerosil) particles is characterized with high-resolution x-ray scattering. The particles form weak gels in 8CB creating a quenched disorder that replaces the transition with the growth of short range smectic correlations. The correlations include thermal critical fluctuations that dominate at high temperatures and a second contribution that quantitatively matches the static fluctuations of a random field system and becomes important at low temperatures.

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S. Park, R. L. Leheny, R. J. Birgeneau, J. -L. Gallani, C. W. Garland, G. S. Iannacchione. 2001-12-05. Hydrogen-bonded Silica Gels Dispersed in a Smectic Liquid Crystal: A Random Field XY System. https://doi.org/10.1103/physreve.65.050703

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