Effect of magnetic nanoparticles on the nematic-smectic-A phase transition

Prabir K. Mukherjee*, Amit K. Chattopadhyay

*Corresponding author for this work

Research output: Contribution to journalArticle

Abstract

Recent experiments on mixed liquid crystals have highlighted the hugely significant role of ferromagnetic nanoparticle impurities in defining the nematic-smectic-A phase transition point. Structured around a Flory-Huggins free energy of isotropic mixing and Landau-de Gennes free energy, this article presents a phenomenological mean-field model that quantifies the role of such impurities in analyzing thermodynamic phases, in a mixture of thermotropic smectic liquid crystal and ferromagnetic nanoparticles. First we discuss the impact of ferromagnetic nanoparticles on the isotropic-ferronematic and ferronematic-ferrosmectic phase transitions and their transition temperatures. This is followed by plotting and discussing various topologies in the phase diagrams. Our model results indicate that there exists a critical concentration of nanoparticle impurities for which the second order N-SmA transition becomes first order at a tricritical point. Calculations based on this model show remarkable agreement with experiment.
Original languageEnglish
Pages (from-to)612-617
Number of pages6
JournalJournal of Molecular Liquids
Volume242
Early online date18 Jul 2017
DOIs
Publication statusPublished - Sep 2017

Fingerprint

Phase transitions
Nanoparticles
nanoparticles
Impurities
impurities
Free energy
free energy
liquid crystals
Thermotropic liquid crystals
Smectic liquid crystals
Liquid Crystals
plotting
mixed crystals
transition points
Liquid crystals
Superconducting transition temperature
Phase diagrams
topology
Experiments
transition temperature

Bibliographical note

© 2017, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/

Keywords

  • liquid crystals
  • nanoparticles
  • phase transition

Cite this

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Effect of magnetic nanoparticles on the nematic-smectic-A phase transition. / Mukherjee, Prabir K.; Chattopadhyay, Amit K.

In: Journal of Molecular Liquids, Vol. 242, 09.2017, p. 612-617.

Research output: Contribution to journalArticle

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