Journal ArticleDOI
Calorimetric study of octylcyanobiphenyl liquid crystal confined to a controlled-pore glass.
TLDR
The heat-capacity response at the weakly first order I-N and continuous N-SmA phase transitions gradually approaches the tricritical-like and three-dimensional XY behavior, respectively.Abstract:
We present a calorimetric study of the phase behavior of octylcyanobiphenyl (8CB) liquid crystal confined to a controlled-pore glass (CPG). We used CPG matrices with characteristic void diameters ranging from 400 to 20 nm. In bulk we obtain weakly first-order isotropic to nematic (I-N) phase transition and nearly continuous character of the nematic to smectic-A (N-SmA) phase transition. In all CPG matrices the I-N transition remains weakly first order, while the N-SmA one becomes progressively suppressed with decreasing CPG pore radius. With decreased pore diameters both phase transition temperatures monotonously decrease following similar trends, but increasing the stability range of the N phase. The heat-capacity response at the weakly first order I-N and continuous N-SmA phase transitions gradually approaches the tricritical-like and three-dimensional XY behavior, respectively. The main observed features were explained using a bicomponent single pore type phenomenological model.read more
Citations
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Journal ArticleDOI
Structure and dynamics of a Gay–Berne liquid crystal confined in cylindrical nanopores
TL;DR: Gay-Berne liquid crystals confined in two cylindrical nanopores with different pore sizes studied by molecular dynamics simulation show that confinement changes the bulk isotropic-to-nematic transition to a continuous ordering from a paranematic to a nematic phase.
Journal ArticleDOI
Calorimetric and dielectric studies of ferroelectric sodium nitrite confined in a nanoscale porous glass matrix.
Zdravko Kutnjak,B. Vodopivec,Robert Blinc,Alexander V. Fokin,Yuri A. Kumzerov,Sergey Vakhrushev +5 more
TL;DR: Heat-capacity measurements of the sodium nitrite confined in a nanoscale porous glass matrix show that the intermediate incommensurate phase, present in the bulk, has disappeared and that the first-order ferroelectric transition becomes suppressed and gradual.
Journal ArticleDOI
Effects of magnetic nanoparticles with different surface coating on the phase transitions of octylcyanobiphenyl liquid crystal.
TL;DR: The impact of magnetic nanoparticles with different surface coating upon the isotropic-to-nematic and nematic- to-smectic- A phase transitions of the liquid crystal octylcyanobiphenyl is explored by means of high-resolution adiabatic scanning calorimetry, and a shrinkage of the nematic range is observed.
Journal ArticleDOI
Direct Measurements of the Electrocaloric Effect in Bulk PbMg1/3Nb2/3O3 (PMN) Ceramics
TL;DR: In this article, the authors used direct measurements of ECE in PMN ceramics near the electric field-induced ferroelectric phase transition to show the existence of the giant ECE.
Journal ArticleDOI
Indirect and direct electrocaloric measurements of (Ba1−xCax)(Zr0.1Ti0.9)O3 ceramics (x = 0.05, x = 0.20)
H. Kaddoussi,H. Kaddoussi,Abdelilah Lahmar,Yaovi Gagou,B. Asbani,J.-L. Dellis,G. Cordoyiannis,B. Allouche,Hamadi Khemakhem,Zdravko Kutnjak,M. El Marssi +10 more
TL;DR: In this paper, the effect of lead-free (Ba1−xCax) (Zr0.1Ti0.9) O3 ceramics on the reciprocal effect of pyroelectric coefficient was investigated by using two different indirect methods.
References
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Book
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TL;DR: In this paper, the authors define an order parameter statistical theories of the nematic order phenomonological description of the nematic-isotopic mixtures and describe the properties of these mixtures.
Journal ArticleDOI
First-Order Phase Transitions in Superconductors and Smectic- A Liquid Crystals
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TL;DR: In this paper, the authors provide a current treatise of the subject matter and places it in the broader context of electrooptic applications, taking an interdisciplinary approach to the subject, combining basic principles of physics, chemistry, polymer science, materials science and engineering.
Journal ArticleDOI
Temperature dependence of the enthalpy and the heat capacity of the liquid-crystal octylcyanobiphenyl (8CB)
TL;DR: In this paper, an adiabatic scanning calorimeter has been used to study the thermal behavior of the liquid-crystal octylcyanobiphenyl (8CB) in the temperature range between 10 and 50°C.
Journal ArticleDOI
Universality and Scaling in the Disordering of a Smectic Liquid Crystal
TL;DR: Experimental and theoretical studies of the effects of quenched disorder on one-dimensional crystal ordering in three dimensions show extended short-range correlations that exhibit universal structure and scaling, anomalous layer elasticity, and glassy dynamics.