Wide temperature range of an electrically tunable selective reflection of light by oblique helicoidal cholesteric

Methylene- and thioether-linked cyanobiphenyl-based liquid crystal dimers CBnSCB exhibiting room temperature twist-bend nematic phases and glasses

“…To date, a wide variety of bent LC dimers, oligomers, 64,[73][74][75][76][77] polymers, 78 and bent-core molecules 79,80 have been found to exhibit the N TB phase. In addition, N TB materials have been used for diverse applications such as photonic and optical devices, [81][82][83][84] gels, 85 elastic bodies, 86 and photoalignment technologies. 87 For characterization and application purposes, it is necessary to develop materials that exhibit the N TB phase over a wide temperature range, the room-temperature N TB phase, and its glass phase or N TB glass (N TB G).…”

Distinct twist-bend nematic phase behaviors associated with the ester-linkage direction of thioether-linked liquid crystal dimers

“…18 Several techniques, including electro-optical measurements, 19 freeze-fracture transmission electron microscopy, 20,21 and resonant soft, hard, and tender X-ray scattering measurements, [22][23][24][25][26][27] suggest that the helical pitch of an N TB phase formed by several molecules is B10 nm, which is significantly shorter than the pitch of a typical chiral N phase or cholesteric phase exhibiting a helicoidal helix (generally hundreds of nanometers). Materials that exhibit the N TB phase have been employed for various LC applications, such as wavelength-tunable selective light reflection [28][29][30][31] and optical memory 32 devices, LC physical gels, 33 photo-switchable viscoelastic bodies, 34 and photoalignment technology. 35 To date, a number of bent LC dimers composed of two mesogenic structures connected with an odd-numbered oligomethylene spacer have been shown to exhibit the N TB phase.…”

Ether‐ and Thioether‐Linked Naphthalene‐Based Liquid‐Crystal Dimers: Influence of Chalcogen Linkage and Mesogenic‐Arm Symmetry on the Incidence and Stability of the Twist–Bend Nematic Phase

“…[30] The N TB liquid crystalsh ave successfully been employedf or photonic applications. [31][32][33] Furthermore, twist-bends mectic (Sm TB ) [34,35] and twist-grain boundary-twist-bend( TGB TB ) [36] phases structurally related to the N TB phase have also been reported. Merkel et al experimentally demonstrated the electrically induced splay-bend nematic( N SB )p hase transition from the N TB phase for ab ent-core molecule [37] and the bent-shaped dimer CB7CB.…”

“…Although the majority of twist–bend nematogens developed so far are achiral, there have been a few reports on formation of the N TB phase based on chiral bent‐shaped molecules, in which the chirality is located in the mesogenic‐arm core, terminal chain, or spacer . The N TB liquid crystals have successfully been employed for photonic applications . Furthermore, twist–bend smectic (Sm TB ) and twist–grain boundary–twist–bend (TGB TB ) phases structurally related to the N TB phase have also been reported.…”