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arXiv · 2211.04432

Continuous Isotropic-Nematic transition in compressed rod-like based nanocolloid

Joanna Łoś·Aleksandra Drozd-Rzoska·Sylwester J. Rzoska·Szymon Starzonek Krzysztof Czupryński·Prabir Mukherjee
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Abstract

Landau - de Gennes mean field model predicts the discontinuous transition for the Isotropic - Nematic transition, associated with uniaxial and quadrupolar order parameter in three dimensions. This report shows pressure-related dielectric studies for rod-like nematogenic pentylcyanobiphenyl (5CB) and its nanocolloids with BaTiO3 nanoparticles. The scan of dielectric constant revealed the continuous I-N transition in a compressed nanocolloid with a tiny amount of nanoparticles (x=0.1%). For the nematic phase in 5CB and its x=1% nanocolloid the enormous values of dielectric constant and the bending-type long-range pretransitional behavior were detected. The 'shaping' influence of pretransitional fluctuations was also detected for the ionic-related contribution to dielectric permittivity in the isotropic phase. For the high-frequency relaxation domain, this impact was tested for the primary relaxation time and the translational-orientaional decoupling.

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Joanna Łoś, Aleksandra Drozd-Rzoska, Sylwester J. Rzoska, Szymon Starzonek Krzysztof Czupryński, Prabir Mukherjee. 2022-11-08. Continuous Isotropic-Nematic transition in compressed rod-like based nanocolloid. https://arxiv.org/abs/2211.04432

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