https://doi.org/10.1140/epje/s10189-022-00228-9
Regular Article - Soft Matter
The impact of ionic contribution to dielectric permittivity in 11CB liquid crystal and its colloids with BaTiO3 nanoparticles
1
Institute of High Pressure Physics, Polish Academy of Sciences, X-PressMatter Lab, ul. Sokołowska 29/37, 01-142, Warsaw, Poland
2
Faculty of Advanced Technologies and Chemistry, Military University of Technology, ul. gen. Sylwestra Kaliskiego 2, 00-908, Warsaw, Poland
Received:
24
May
2022
Accepted:
24
August
2022
Published online:
8
September
2022
The report shows the temperature behavior of the real part of dielectric permittivity in the static (dielectric constant) and low-frequency (LF) domains in bulk samples of 11CB and its BaTiO3-based nanocolloids. The study covers the isotropic liquid (I), nematic (N), smectic A (SmA), and solid crystal (Cr) phases. For each phase, the dominance of pretransitional fluctuations, significantly moderated by nanoparticles, is shown. The authors consider separate focuses on the dielectric constant ε(T) evolution in the static domain, yielding mainly response from permanent dipole moment and its arrangement, and in the low-frequency (LF) domain Δε′(f) = ε′(f)-ε (where ε′(f) is for the real part of dielectric permittivity in the LF domain), which is associated solely with ionic-related polarization mechanisms. All of these led to new experimental evidence concerning I–N, N–SmA, and SmA–solid transitions, focusing on the strength and extent of pretransitional effects, critical exponents, and phase transitions discontinuities. The strong evidence for pretransitional effects near the SmA–Cr transition is notable, particularly regarding Δε′(f,T). Studies are supplemented by the discussion of DC electric conductivity—a parameter also related to the LF domain. Finally, the validity of the relation ε′(f)=Af-3/2+ε (where f stands for frequency, and A is a constant parameter), often used for discussing dielectric spectra in LC compound and its nanocolloids in the LF domain, is examined.
Soft Matter and Food. Guest editors: Fabrizio Croccolo, Aleksandra Drozd-Rzoska, Samo Kralj, Szymon Starzonek.
© The Author(s) 2022
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
