The European Physical Journal E ( IF 1.8 ) Pub Date : 2022-09-08 , DOI: 10.1140/epje/s10189-022-00228-9 Joanna Łoś 1 , Aleksandra Drozd-Rzoska 1 , Sylwester J Rzoska 1 , Krzysztof Czupryński 2
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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 \(\varepsilon \left( {\varvec{T}} \right)\) evolution in the static domain, yielding mainly response from permanent dipole moment and its arrangement, and in the low-frequency (LF) domain \(\Delta \varepsilon^{\prime } \left( f \right) = \varepsilon^{\prime } \left( f \right) - \varepsilon\) (where \(\varepsilon^{\prime } \left( {\varvec{f}} \right)\) 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 \(\Delta \varepsilon^{\user2{^{\prime}}} \left( {{\varvec{f}},{\varvec{T}}} \right)\). Studies are supplemented by the discussion of DC electric conductivity—a parameter also related to the LF domain. Finally, the validity of the relation \(\varepsilon^{\prime } \left( {\varvec{f}} \right) = {\varvec{Af}}^{ - 3/2} + \varepsilon\) (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.
Graphical abstract
中文翻译：
离子贡献对 11CB 液晶及其胶体与 BaTiO3 纳米粒子介电常数的影响
该报告显示了 11CB 及其 BaTiO 3基纳米胶体大块样品中介电常数实部在静态（介电常数）和低频（LF）域中的温度行为。该研究涵盖各向同性液体 (I)、向列 (N)、近晶 A (SmA) 和固晶 (Cr) 相。对于每个阶段，显示了由纳米粒子显着缓和的过渡前波动的主导地位。作者认为单独关注介电常数\(\varepsilon \left( {\varvec{T}} \right)\)在静态域中的演变，主要产生来自永久偶极矩及其排列的响应，在低-频域 (LF)\(\Delta \varepsilon^{\prime } \left( f \right) = \varepsilon^{\prime } \left( f \right) - \varepsilon\)（其中\(\varepsilon^{\prime } \ left( {\varvec{f}} \right)\)是 LF 域中介电常数的实部），它仅与离子相关的极化机制相关。所有这些都导致了关于 I-N、N-SmA 和 SmA-固体转变的新实验证据，重点关注转变前效应、临界指数和相转变不连续性的强度和程度。在 SmA–Cr 过渡附近的过渡前效应的有力证据是值得注意的，特别是关于\(\Delta \varepsilon^{\user2{^{\prime}}} {T}}} \right)\). 研究补充了对直流电导率的讨论——一个也与 LF 域相关的参数。最后，关系的有效性\(\varepsilon^{\prime } \left( {\varvec{f}} \right) = {\varvec{Af}}^{ - 3/2} + \varepsilon\) (其中f代表频率，A是常数参数），通常用于讨论 LC 化合物及其在 LF 域中的纳米胶体中的介电光谱。
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