English
Related papers

Related papers: Do the short helices exist in the nematic TB phase…

200 papers

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

Using a novel Se-labelled dimer mixed with DTC5C7 aligned by magnetic field, the twist-bend nematic phase (Ntb) in dimers was studied by hard X-ray resonant scattering and by small and wide angle X-ray scattering (SAXS, WAXS). Resonant…

Soft Condensed Matter · Physics 2017-06-28 W. D. Stevenson , Z. Ahmed , X. B. Zeng , C. Welch , G. Ungar , G. H. Mehl

We report a dynamic light scattering study of the fluctuation modes in a thermotropic liquid crystalline mixture of monomer and dimer compounds that exhibits the twist-bend nematic ($\mathrm{N_{TB}}$) phase. The results reveal a spectrum of…

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

NMR measurements on a selectively deuteriated liquid crystal dimer CB-C9-CB exhibiting two nematic phases show that the molecules in the lower temperature nematic phase, Nx, experience a chiral environment and are ordered about a unique…

Soft Condensed Matter · Physics 2014-07-09 Anke Hoffmann , Alexandros G. Vanakaras , Alexandra Kohlmeier , Georg H. Mehl , Demetri J. Photinos

The extended Frank elastic energy density is used to investigate the existence of a stable periodically modulate structure that appears as a ground state exhibiting a twist-bend molecular arrangement. For an unbounded sample, we show that…

Soft Condensed Matter · Physics 2017-06-01 M. P. Rosseto , R. R. Ribeiro de Almeida , R. S. Zola , G. Barbero , I. Lelidis , L. R. Evangelista

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,…

Molecular dynamics simulations of selected members of the cyano-biphenyl series of dimers (CBnCB) have been set up using atomistic detail interactions among intermolecular pairs of united atoms and allowing fully for the flexibility of the…

Soft Condensed Matter · Physics 2019-08-06 Alexandros G. Vanakaras , Demetri J. Photinos

Helical structures are exciting and are utilized in numerous applications ranging from biotechnology to displays to medicine. Accurate description and understanding of resonance effects in helical structures provides crucial knowledge on…

Soft Condensed Matter · Physics 2020-02-04 Yu Cao , Jun Feng , Asritha Nallapaneni , Yuki Arakawa , Keqing Zhao , Georg H. Mehl , Feng Liu , Chenhui Zhu

The critical behavior at the transition from uniform nematic to twist-bend modulated nematic phase is revealed and shown to be well explained by the mean field approximation. The study was performed on a group of materials that exhibit an…

Spontaneous formation of polarization gratings by liquid crystals made of bent dimeric molecules is reported. The grating is formed within the temperature range of the twist bend modulated nematic phase, NTB, without the necessity to…

Soft Condensed Matter · Physics 2018-04-12 N. Vaupotič , M. Ali , P. W. Majewski , E. Gorecka , D. Pociecha

A number of highly polar three ring rod-shaped compounds with a terminal thiophene ring have been synthesized and the physical properties of a subset are reported in detail. On cooling from the isotropic fluid, they directly transition to a…

Resonant x-ray scattering shows that the bulk structure of the twist-bend liquid crystal phase, recently discovered in bent molecular dimers, has spatial periodicity without electron density modulation, indicating a lattice-free heliconical…

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

We predict the existence of a new defect-lattice phase near the nematic - smectic-C (NC) transition. This tilt- analogue of the blue phase is a lattice of double-tilt cylinders. We discuss the structure and stability of the cone phase. We…

Soft Condensed Matter · Physics 2009-11-07 Yashodhan Hatwalne , N. V. Madhusudana

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 twist-bend nematic (N\textsubscript{TB}) liquid crystals (LCs), the mean molecular orientation exhibits heliconical structure with nanoscale periodicity. On the mesoscopic scale, N\textsubscript{TB} resembles layered systems (like…

Soft Condensed Matter · Physics 2020-11-25 M. Praveen Kumar , P. Kula , Surajit Dhara

A system that possesses translational symmetry but breaks orientational symmetry is known as a nematic phase. While there are many examples of nematic phases in a wide range of contexts, such as in liquid crystals, complex oxides, and…

Small-angle neutron scattering (SANS) profiles revealed the existence of magnetic textures like liquid crystals in the low-temperature helical phase of Fe0.7Co0.3Si, isomorphous of MnSi.

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…