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Related papers: 'Setting things straight' by twisting and bending?

200 papers

Dielectric spectroscopy of a twist bend nematic phase of an achiral bent core liquid crystalline compound under DC bias is used to investigate its response to electric field. Two collective relaxation processes are revealed, these are…

Soft Condensed Matter · Physics 2018-09-12 K. Merkel , A. Kocot , J. K. Vij , G. Shanker

Certain nematic liquid crystals, e.g., those formed by banana-shaped molecules, can exhibit a low-temperature twist-bend nematic (Ntb) phase. Upon addition of chiral dopants, a chiral version of the twist-bend phase (N*tb) can be observed…

Soft Condensed Matter · Physics 2021-09-08 Natalia Kasian , Longin Lisetski , Igor Gvozdovskyy

Freeze Fracture Transmission Electron Microscopy (FFTEM) study of the nanoscale structure of the so-called "twist-bend" nematic (NX) phase of the cyanobiphenyl (CB) dimer molecule CB(CH2)7CB reveals a stripe texture of fluid layers…

Different liquid crystalline phases with long-range orientational but not positional order, so-called nematic phases, are scarce. It rarely occurs that a new nematic phase is discovered and such event is inevitably accompanied by a great…

The possible symmetries of the biaxial nematic phase are examined against the implications of the presently available experimental results. Contrary to the widespread notion that biaxial nematics have orthorhombic symmetry, our study shows…

Soft Condensed Matter · Physics 2010-04-15 Panagiota K. Karahaliou , Alexandros G. Vanakaras , Demetri J. Photinos

Spontaneous symmetry breaking and emergent polar order are each of fundamental importance to a range of scientific disciplines, as well as generating rich phase behaviour in liquid crystals (LCs). Here, we show the union of these phenomena…

Soft Condensed Matter · Physics 2024-08-06 Calum Gibb , Jordan Hobbs , Diana Nikolova , Tom Raistrick , Helen Gleeson , Richard Mandle

We study the symmetry and the spatial uniformity of orientational order of the biaxial nematic phase in the light of recent experimental observations of phase biaxiality in thermotropic bent-core and calamitic-tetramer nematics. We present…

Soft Condensed Matter · Physics 2010-04-15 Stavros D. Peroukidis , Panagiota K. Karahaliou , Alexandros G. Vanakaras , D. J. Photinos

The relationship between the molecular structure and the formation of the NTB phase is still at an early stage of development. This is mainly related to molecular geometry, while the correlation between the NTB phase and the electronic…

Chemical Physics · Physics 2021-01-04 Katarzyna Merkel , Barbara Loska , Chris Welch , Georg H. Mehl , Antoni Kocot

In two dimensional nematics, topological defects are point like singularities with both a charge and a phase. We study topological defects within curved nematic textures on the surface of a cylinder. This allows us to isolate the effect of…

Soft Condensed Matter · Physics 2022-05-10 Daniel J. G. Pearce

In liquid crystals, if flexoelectric couplings between polar order and director gradients are strong enough, the uniform nematic phase can become unstable to formation of a modulated polar phase. Previous theories have predicted two types…

Soft Condensed Matter · Physics 2018-06-21 Shaikh M. Shamid , David W. Allender , Jonathan V. Selinger

The nematic ordering in semiflexible polymers with contour length $L$ exceeding their persistence length $\ell_p$ is described by a confinement of the polymers in a cylinder of radius $r_{eff}$ much larger than the radius $r_\rho$, expected…

Soft Condensed Matter · Physics 2016-05-11 Sergei A. Egorov , Andrey Milchev , Kurt Binder

The recent experimental discovery of ferroelectric and splay nematic phases has sparked interest in comprehending the crucial molecular features necessary to stabilize these innovative structures. This study advances the ongoing discourse…

Soft Condensed Matter · Physics 2024-09-17 Agnieszka Chrzanowska , Lech Longa

Infrared spectroscopy (IR) and quantum chemistry calculations, based on density functional theory (DFT) were used to study the structure and the molecular interactions in the nematic (N) and twist-bend (NTB) phases of thioether-linked…

Soft Condensed Matter · Physics 2022-06-16 Katarzyna Merkel , Barbara Loska , Yuki Arakawa , Georg H. Mehl , Jakub Karcz , Antoni Kocot

We explore surface alignment and edge dislocations in the recently discovered twist-bend ferroelectric nematic, NTBF, in which the vector of spontaneous polarization follows an oblique helicoidal trajectory around a polar twist-bend axis.…

In search for novel nematic materials, a laterally linked H-shaped liquid crystal dimer have been synthesized and characterized. The distinct feature of the material is a very broad temperature range (about 50 oC) of the nematic phase,…

We report on the temperature dependence of birefringence and of the static dielectric permittivity tensor in a series of binary mixtures between the symmetric, bent-shaped, 1",9"-bis(4-cyanobiphenyl-4'-yl) nonane (CB9CB) dimer and the…

Binary mixtures of the twist-bend nematic-forming liquid crystal CB7CB with the prototypical rod-like liquid crystal 5CB exhibit a twist-bend nematic phase with properties similar to those reported for neat CB7CB. The mixtures appear…

We report the properties of two new series of compounds that show the ferroelectric nematic phase in which the length of a terminal chain is varied. The longer the terminal chain, the weaker the dipole-dipole interactions of the molecules…

Both uniaxial and biaxial nematic liquid crystals are defined by orientational ordering of their building blocks. While uniaxial nematics only orient the long molecular axis, biaxial order implies local order along three axes. As the…

Soft Condensed Matter · Physics 2015-06-15 Simon Čopar , Mark R. Dennis , Randall D. Kamien , Slobodan Žumer

Twist-bend (Ntb) and ferroelectric (NF) nematic liquid crystals exhibit several novel effects and new physical properties. The question of what happens in binary mixtures is interesting as a matter of curiosity and pure science. Here, we…

Soft Condensed Matter · Physics 2023-08-07 Abinash Barthakur , Jakub Karcz , Przemyslaw Kula , Surajit Dhara