13 C NMR studies and orientational order of rod-like mesogens with strongly polar terminal cyano group DOI

M. Kesava Reddy,

Yanati Santhosh Kumar Reddy,

Nitin P. Lobo

et al.

Liquid Crystals, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 17

Published: Oct. 30, 2024

Language: Английский

Systematic Fluorination Is a Powerful Design Strategy toward Fluid Molecular Ferroelectrics DOI Creative Commons
Calum J. Gibb, Jordan Hobbs, Richard J. Mandle

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 24, 2025

Ferroelectric nematic (NF) liquid crystals combine liquid-like fluidity and orientational order of conventional nematics with macroscopic electric polarization comparable in magnitude to solid-state ferroelectric materials. Here, we present a systematic study twenty-seven homologous materials various fluorination patterns, giving new insight into the molecular origins spontaneous polar ordering fluid nematics. Beyond our initial expectations, find highest stability NF phase be specific patterns rather than maximal fluorination, which might expected based on simple models. We delicate balance between apolar nematics, is entirely dictated by substitution fluorine atoms. Aided electronic structure calculations, show this have its radial distribution charge across surface, molecules possessing more oscillatory electrons their surfaces higher propensity form phases. This work provides set ground rules design principles that can inform synthesis future nematogens.

Language: Английский

Citations

7

Fluorination: Simple Change but Complex Impact on Ferroelectric Nematic and Smectic Liquid Crystal Phases DOI Creative Commons
Grant J. Strachan, Ewa Górecka, Jordan Hobbs

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

A series of liquid crystal (LC) materials are reported, which form a variety ferroelectric nematic and smectic phases. The relationship between the number position lateral fluorine substituents formation LC phases is investigated. While addition increases temperature at order appears, fluorination phase sequence more complicated. Introducing can either suppress or promote phases, depending on their within molecule, interplay these trends allows for exotic to appear.

Language: Английский

Citations

4

Emergent Antiferroelectric Ordering and the Coupling of Liquid Crystalline and Polar Order DOI Creative Commons
Jordan Hobbs, Calum J. Gibb, Richard J. Mandle

et al.

Small Science, Journal Year: 2024, Volume and Issue: unknown

Published: July 3, 2024

Polar liquid crystals possess 3D orientational order coupled with unidirectional electric polarity, yielding fluid ferroelectrics. Such polar phases are generated by rod‐like molecules large dipole moments. 2,5‐Disubstituted 1,3‐dioxane is commonly employed as a motif in said systems, and herein it shown to suffer from thermal instability consequence of equatorial‐trans axial‐trans isomerism at elevated temperatures. Isosteric building blocks utilized potential replacements for the unit, doing so new examples ferroelectric systems obtained. For binary mixtures certain composition, emergence antiferroelectric phase, finding not observed either parent molecules, observed. This study also reveals critical tipping point otherwise apolar systems. These results hint possibility uncovering highly ordered liquid‐crystalline delineate distinct transition mechanisms ordering.

Language: Английский

Citations

13

Emergent Ferroelectric Nematic and Heliconical Ferroelectric Nematic States in an Achiral “Straight” Polar Rod Mesogen DOI Creative Commons
Hiroya Nishikawa, Daichi Okada, Dennis Kwaria

et al.

Advanced Science, Journal Year: 2024, Volume and Issue: 11(39)

Published: Aug. 5, 2024

Abstract Ferroelectric nematic liquid crystals (N F LCs) are distinguished by their remarkable polarization characteristics and diverse physical phenomena, sparking significant interest excitement within the scientific community. To date, over 150 N LC molecules developed; however, there no reports regarding straight linear polar with a parallel alignment of permanent dipole moment molecular axis. The mesogen nBOE exhibits an enantiotropic phase wide temperature window (up to 100 K) despite having longer alkyl chain n = 6) than critical length conventional models. Interestingly, medium‐length displays exotic sequence – HC –SmX during elimination positional displacement among adjacent molecules. Furthermore, reflective color modulation entire VIS‐NIR spectral regime ultralow E ‐field 0.14 V µm −1 ) is demonstrated.

Language: Английский

Citations

13

Updated view of new liquid-matter ferroelectrics with nematic and smectic orders DOI Creative Commons

Yaohao Song,

Satoshi Aya, Mingjun Huang

et al.

Giant, Journal Year: 2024, Volume and Issue: 19, P. 100318 - 100318

Published: July 4, 2024

The recent discovery of liquid-matter ferroelectrics not only opens a door to explore novel polar matter states and properties in the term condensed physics but also provides unprecedented opportunities for developing new liquid crystal materials technologies. progression from ferroelectric nematic phase many other represents remarkable journey emerging soft matter. In this perspective, we briefly introduce latest quick rise advancements that display smectic characteristics. We summarize recently-discovered phases, their physics, potential technological innovations, then give some hints consider critical further exploration. More importantly, seek delve into broader discussions on chemical structure design, underlying physical interactions driving various states, connections range intriguing phenomena.

Language: Английский

Citations

10

Biphenyl Benzoate Derived Polymorphic Self-Assembling Chalcones: Influence of Mesogenic Core Variations And Terminal Alkyl Chains DOI
Rina Soni, Kiran J. Nakum,

Divyesh Patel

et al.

Journal of Molecular Liquids, Journal Year: 2024, Volume and Issue: 408, P. 125328 - 125328

Published: June 24, 2024

Language: Английский

Citations

3

Revealing the antipolar order in the antiferroelectric SmZA phase by means of circular alignment DOI Creative Commons
Pierre Nacke,

Rachel P. Tuffin,

Melanie Klasen‐Memmer

et al.

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: July 1, 2024

Abstract Many ferroelectric nematic liquid crystals, like one of the archetype materials, DIO, do not have a direct paraelectric N to F phase transition, but exhibit yet another between and . This has recently been proposed be antiferroelectric, with layered structure alternating polarization normal average director is sometimes referred as Smectic Z A (SmZ ). We examined SmZ in circularly rubbed (CR) cells, known discriminate polar non-polar from configuration disclination lines formed. find that ground state same phase, demonstrating also non-polar, i.e., it no net polarization. At time, texture generally grainy appearance, which we suggest partly result frustration related order combined imposed twist CR cells. discuss possible orientations smectic layers, depending on alignment conditions. While horizontal layer always compatible surface-induced twist, vertical would tend break up twisted bookshelf match non-parallel directions at two surfaces.

Language: Английский

Citations

3

A design approach to obtaining highly polar liquid crystal dimers DOI Creative Commons
Amerigo Zattarin, Ewan Cruickshank, Damian Pociecha

et al.

Liquid Crystals, Journal Year: 2024, Volume and Issue: 51(6), P. 1035 - 1046

Published: May 2, 2024

The synthesis and characterisation of 10 members the [4[(E)-[4-[4-[ω-(4-cyanophenyl)phenoxy]alkyloxy]-3-nitrophenyl]methylideneamino]phenyl] 2,4-dimethoxybenzoates is reported in which number methylene units flexible spacer increased from three to twelve. mesogenic are based on cyanobiphenyl 3-nitrobenzylideneaniline benzoate linked by such that their dipoles parallel giving rise a large longitudinal dipole moment. All series show nematic phase, nematic-isotropic transition temperatures, TNI, associated entropy changes strong dependence length parity spacer. This behaviour attributed average shapes molecules flexibility. heptyl member was further characterised using dielectric spectroscopy revealing high value permittivity reflecting moment possibly indicating local short-range ferroelectric order. two [4[(E)-[4-[4-[3-(ω-cyanophenyl)phenoxy]alkyloxy]-4-nitrophenyl]methylideneamino]phenyl] also described for difference shape between odd even reduced. Both dimers exclusively nematogenic TNI smaller more similar molecular shapes. potential developing exhibit phase discussed.

Language: Английский

Citations

3

Colossal Dielectric Permittivity and Superparaelectricity in phenyl pyrimidine based liquid crystals DOI
Yu. P. Panarin, Wanhe Jiang, Neelam Yadav

et al.

Journal of Materials Chemistry C, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Synthesized organic fluids with large longitudinal dipole moments are shown to demonstrate superparaelectricity.

Language: Английский

Citations

3

The role of fluorine substituents on the formation of the ferroelectric nematic phase DOI Creative Commons
Ewan Cruickshank, Rebecca Walker, Grant J. Strachan

et al.

Journal of Materials Chemistry C, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 20, 2024

We report on a series of materials which exhibit range nematic phases including the rare example single compound shows both enantiotropic N X and F phases.

Language: Английский

Citations

3