Pretransitional Effects of the Isotropic Liquid–Plastic Crystal Transition

We report on strong pretransitional effects across the isotropic liquid–plastic crystal melting temperature in linear and nonlinear dielectric response. Studies were carried out for cyclooctanol (C8H16O) in the unprecedented range of temperatures 120 K < T < 345 K. Such pretransitional effects have not yet been reported in any plastic crystals. Results include the discovery of the experimental manifestation of the Mossotti Catastrophe behavior, so far considered only as a hypothetical paradox. The model interpretations of experimental findings are proposed. We compare the observed pretransitional behavior with the one observed in octyloxycyanobiphenyl (8OCB), typical liquid crystal (LC), displaying a reversed sequence of phase transitions in orientational and translational degrees of order on varying temperature. Furthermore, in its nematic phase, we demonstrate first-ever observed temperature-driven crossover between regions dominated by isotropic liquid and smectic A pretransitional fluctuations. We propose a pioneering minimal model describing plastic crystal phase behavior where we mimic derivation of classical Landau-de Gennes-Ginzburg modeling of Isotropic-Nematic-Smectic A LC phase behavior.

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Effect of substituents and anions on the phase behavior of Ru(ii) sandwich complexes: exploring the boundaries between ionic liquids and ionic plastic crystals

Physical Chemistry Chemical Physics ◽

10.1039/c6cp08308k ◽

2017 ◽

Vol 19 (6) ◽

pp. 4352-4359 ◽

Cited By ~ 13

Author(s):

Takumi Tominaga ◽

Takahiro Ueda ◽

Tomoyuki Mochida

Keyword(s):

Ionic Liquids ◽

Phase Behavior ◽

Plastic Crystal ◽

Sandwich Complexes ◽

Plastic Crystals ◽

Effect Of Substituents ◽

Crystal Phases

Salts of cationic ruthenium sandwich complexes bearing ethyl or longer substituents are ionic liquids, whereas salts with shorter substituents showed ionic plastic crystal phases.

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Electrically turning periodic structures in cholesteric layer with conical–planar boundary conditions

Scientific Reports ◽

10.1038/s41598-021-87854-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Oxana Prishchepa ◽

Mikhail Krakhalev ◽

Vladimir Rudyak ◽

Vitaly Sutormin ◽

Victor Zyryanov

Keyword(s):

Boundary Conditions ◽

Periodic Structures ◽

Cholesteric Liquid Crystal ◽

Growth Direction ◽

Smooth Transition ◽

Defect Structures ◽

Optical Cell ◽

Elastic Continuum ◽

The One ◽

Experimental Findings

AbstractElectro-optical cell based on the cholesteric liquid crystal is studied with unique combination of the boundary conditions: conical anchoring on the one substrate and planar anchoring on another one. Periodic structures in cholesteric layer and their transformation under applied electric field are considered by polarizing optical microscopy, the experimental findings are supported by the data of the calculations performed using the extended Frank elastic continuum approach. Such structures are the set of alternating over- and under-twisted defect lines whose azimuthal director angles differ by $$180^\circ$$ 180 ∘ . The $$U^+$$ U + and $$U^-$$ U - -defects of periodicity, which are the smooth transition between the defect lines, are observed at the edge of electrode area. The growth direction of defect lines forming a diffraction grating can be controlled by applying a voltage in the range of $$0\le \, V \le 1.3$$ 0 ≤ V ≤ 1.3 V during the process. Resulting orientation and distance between the lines don’t change under voltage. However, at $$V>1.3$$ V > 1.3 V $$U^+$$ U + -defects move along the defect lines away from the electrode edges, and, finally, the grating lines collapse at the cell’s center. These results open a way for the use of such cholesteric material in applications with periodic defect structures where a periodicity, orientation, and configuration of defects should be adjusted.

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Predicting gas selectivity in organic ionic plastic crystals by free energy calculations

RSC Advances ◽

10.1039/d1ra01844b ◽

2021 ◽

Vol 11 (32) ◽

pp. 19623-19629

Author(s):

Vinay S. Kandagal ◽

Jennifer M. Pringle ◽

Maria Forsyth ◽

Fangfang Chen

Keyword(s):

Free Energy ◽

Gas Separation ◽

Free Energy Calculations ◽

Free Energy Calculation ◽

Energy Calculation ◽

Plastic Crystal ◽

Plastic Crystals ◽

New Type ◽

Gas Molecules ◽

Gas Selectivity

The free energy calculation shows the different free energy changes of the adsorption and absorption of gas molecules into an organic ionic plastic crystal, successfully predicting the gas selectivity of this new type of gas separation material.

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Quantum teleportation with imperfect quantum dots

npj Quantum Information ◽

10.1038/s41534-020-00356-0 ◽

2021 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

F. Basso Basset ◽

F. Salusti ◽

L. Schweickert ◽

M. B. Rota ◽

D. Tedeschi ◽

...

Keyword(s):

Quantum Dots ◽

Quantum Teleportation ◽

Bell State ◽

Spectral Filtering ◽

State Measurement ◽

Communication Architectures ◽

The One ◽

Experimental Findings ◽

Photon Source ◽

Remarkable Progress

AbstractEfficient all-photonic quantum teleportation requires fast and deterministic sources of highly indistinguishable and entangled photons. Solid-state-based quantum emitters—notably semiconductor quantum dots—are a promising candidate for the role. However, despite the remarkable progress in nanofabrication, proof-of-concept demonstrations of quantum teleportation have highlighted that imperfections of the emitter still place a major roadblock in the way of applications. Here, rather than focusing on source optimization strategies, we deal with imperfections and study different teleportation protocols with the goal of identifying the one with maximal teleportation fidelity. Using a quantum dot with sub-par values of entanglement and photon indistinguishability, we show that the average teleportation fidelity can be raised from below the classical limit to 0.842(14), adopting a polarization-selective Bell state measurement and moderate spectral filtering. Our results, which are backed by a theoretical model that quantitatively explains the experimental findings, loosen the very stringent requirements set on the ideal entangled-photon source and highlight that imperfect quantum dots can still have a say in teleportation-based quantum communication architectures.

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INDUCED CHANGES OF THERMOTROPIC PROPERTIES OF PHASE TRANSITIONS BETWEEN SMECTIC A MESOPHASE AND ISOTROPIC LIQUID: EFFECT OF SURFACES

Modern Physics Letters B ◽

10.1142/s0217984906010755 ◽

2006 ◽

Vol 20 (14) ◽

pp. 821-833 ◽

Cited By ~ 7

Author(s):

ARIF NESRULLAJEV ◽

ŞENER OKTIK

Keyword(s):

Thin Film ◽

Thin Films ◽

Phase Transition ◽

Phase Transitions ◽

Isotropic Liquid ◽

Smectic A ◽

Phase Transition Temperatures ◽

Smectic A Phase ◽

Induced Changes ◽

Thermotropic Properties

In this work, the effect of thin films on the thermotropic and thermo-optical properties and peculiarities of the phase transitions between the smectic A and isotropic liquid have been investigated. Peculiarities of the heterophase regions of the straight smectic A-isotropic liquid and reverse isotropic liquid-smectic A phase transitions have been studied. Change of morphologic properties of the heterophase regions, shift of the phase transition temperatures and the change of temperature widths of these heterophase regions under thin film influence have been observed.

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Temperature Dependence of the Dielectric Constant Calculated Using a Mean Field Model Close to the Smectic A - Isotropic Liquid Transition

Ferroelectrics - Characterization and Modeling ◽

10.5772/16529 ◽

2011 ◽

Author(s):

H. Yurtseven ◽

E. Kilit

Keyword(s):

Dielectric Constant ◽

Temperature Dependence ◽

Field Model ◽

Mean Field ◽

Mean Field Model ◽

Isotropic Liquid ◽

Smectic A ◽

Liquid Transition

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Formation of a solid solution between [N(C2H5)4][BF4] and [N(C2H5)4][PF6] in crystal and plastic crystal phases

Physical Chemistry Chemical Physics ◽

10.1039/c6cp07992j ◽

2017 ◽

Vol 19 (3) ◽

pp. 2053-2059 ◽

Cited By ~ 6

Author(s):

Kazuhiko Matsumoto ◽

Ryojun Nonaka ◽

Yushen Wang ◽

Gleb Veryasov ◽

Rika Hagiwara

Keyword(s):

Solid Solution ◽

Binary System ◽

Rock Salt ◽

Plastic Crystal ◽

Plastic Crystals ◽

System Form ◽

Crystal Phases ◽

Form Solid Solution

The [N(C2H5)4][BF4]–[N(C2H5)4][PF6] binary system form solid solution in both crystal and plastic crystal phases (rock-salt type for plastic crystals).

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Average Droplet Diameter Spatial Distribution in a Spray After Gas-Assisted Atomization

Volume 7: Fluid Flow, Heat Transfer and Thermal Systems, Parts A and B ◽

10.1115/imece2010-39737 ◽

2010 ◽

Cited By ~ 1

Author(s):

Konstantin Pougatch ◽

Martha Salcudean ◽

Jennifer McMillan

Keyword(s):

Droplet Diameter ◽

Particle Diameter ◽

Droplet Size Distribution ◽

Average Diameter ◽

Diameter Distribution ◽

Nozzle Orifice ◽

Average Value ◽

Local Mean ◽

The One ◽

Experimental Findings

Gas-assisted atomization is used in many industries to produce finely dispersed droplets. Knowledge about the droplet size distribution guides the design and development of the nozzle as well as of the whole processes. This knowledge can be obtained through experimental and modeling works that usually complement each another. In this paper we present an application of the mathematical model previously developed for gas-assisted atomization to the prediction of the average droplet diameter distribution in a spray and compare the results with experimental findings. The model is based on a two-fluid Eulerian-Eulerian treatment of the motion of the phases with a catastrophic phase inversion (atomization). It also includes the compressibility effects for the gaseous phase and can be applied to both the flow through the nozzle-atomizer and to the dispersion of the spray. The model accounts for the break-up and coalescence of bubbles and droplets due to interfacial shear and collisions. The diameter of the particle (bubble or droplet) is represented by its local mean average value that varies throughout the flow field. Simulations are conducted for the flow of air and water through the convergent-divergent nozzle, which is similar to the one used in commercial fluid cokers, a bitumen upgrading apparatus, for steam-assisted atomization of bitumen. It is found that while there are wide experimentally observed local distributions of the particle diameter, the concept of the average diameter still allows for satisfactory predictions of its average values and spatial variations. In agreement with the experiments, the numerical model demonstrated that the largest droplet diameter is located in the axial area, and the diameter values reduce towards the periphery of the jet. In addition, the average diameter increases slightly and its radial variation becomes more uniform as the distance from the nozzle orifice increases.

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