相关论文: The Twist Bend Nematic: A Case of Mistaken Identit…
The understanding of self-organization in the twist-bend nematic $(N_\text{TB})$ phase, identified in 2011 in liquid crystal dimers, is at the forefront of soft matter research worldwide. This new nematic phase develops structural chirality…
The recently discovered twist-bend nematic phase, $\rm N_{tb}$, is a non-uniform equilibrium nematic phase that presents a spontaneous bend with a precession of the nematic director, $\textbf{n}$, on a conical helix with a tilt angle…
The twist-bend nematic phase, $N_{\rm TB}$, may be viewed as a heliconical molecular arrangement in which the director $\bf n$ precesses uniformly about an extra director field, $\bf t$. It corresponds to a nematic ground state exhibiting…
The twist-bend nematic (Ntb) phase is a recent addition to the nematic (N) phases of liquid crystals (LCs). A net polar order in the Ntb phase under an external electric field was predicted in several recent theoretical studies but yet to…
The nematic twist-bend ($\mathrm{N_{TB}}$) phase, exhibited by certain thermotropic liquid crystalline (LC) dimers, represents a new orientationally ordered mesophase -- the first distinct nematic variant discovered in many years. The…
The ground state of twist-bend nematic liquid crystals is a heliconical molecular arrangement in which the nematic director precesses uniformly about an axis, making a fixed angle with it. Both precession senses are allowed in the ground…
Photo-polymerization of a reactive mesogen mixed with a mesogenic dimer, shown to exhibit the twist-bend nematic phase ($N_{TB}$), reveals the complex structure of the self-deformation patterns observed in planar cells. The polymerized…
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…
The nematic twist-bend (TB) phase, exhibited by certain achiral thermotropic liquid crystalline (LC) dimers, features a nanometer-scale, heliconical rotation of the average molecular long axis (director) with equally probable left- and…
An analysis of the IR absorbance for the segmented functional groups of liquid crystal dimers: mesogen and linker, enabled the orientation order to be determined and information about the dipole interactions in the nematic and twist-bend…
A state of matter in which molecules show a long-range orientational order and no positional order is called a nematic liquid crystal. The best known and most widely used (for example, in modern displays) is the uniaxial nematic, with the…
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…
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…
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…
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…
We present a simplified molecular model of mesogenic dimers consisting of two identical uniaxial mesogenic cores separated by a fixed-length spacer and allowed to assume only two, statistically equivalent, conformations which are non-planar…
We explain the origins of the controversy about the classification of the $N_X$ phase observed in cyanobiphenyl dimers and why it is a polar twisted phase, an entirely new kind of nematic.
Nematic twist--bend is the fifth nematic phase recognized in nature. This phase exhibits spiral orientational order, thus it is a chiral structure and it can be stabilized in systems composed of achiral molecules. The microscopic origin of…
The nonlinear elastic properties of nematic liquid crystals have acquired new interest with the recent experimental observation of bulk modulated nematic phases which are composed by achiral molecules. We extend the Oseen-Zocher-Frank's…
X-ray scattering and polarized microscopic studies of the structure and order parameters in the nematic (N) and heliconical, or the twist-bend nematic (Ntb), phase have been performed as a function of temperature. The nematic orientational…