Abstract
The twist‐bend nematic, NTB, phase has been observed for chiral materials in which chirality is introduced through a branched 2‐methylbutyl terminal tail. The chiral twist‐bend nematic phase, N*TB, is completely miscible with the NTB phase of the standard achiral material, CB6OCB. The N*TB phase exhibits optical textures with lower birefringence than those observed for the achiral NTB phase, suggesting an additional mechanism of averaging molecular orientations. The N*−N*TB transition temperatures for the chiral materials are higher than the NTB−N transition temperatures seen for the corresponding racemic materials. This suggests the double degeneracy of helical twist sense in the phase is removed by the intrinsic molecular chirality. A square lattice pattern is observed in the N* phase over a temperature range of several degrees above the N*TB–N phase transition, which may be attributed to a non‐monotonic dependence of the bend elastic constant.
| Original language | English |
|---|---|
| Pages (from-to) | 13329-13335 |
| Number of pages | 7 |
| Journal | Chemistry : a European Journal |
| Volume | 25 |
| Issue number | 58 |
| Early online date | 5 Sept 2019 |
| DOIs | |
| Publication status | Published - 17 Oct 2019 |
Bibliographical note
AcknowledgementsE.G. and D.P. acknowledge the support of the National Science Centre (Poland): (Grant Number 2016/22/A/ST5/00319). R.W. gratefully acknowledges The Carnegie Trust for the Universities of Scotland for funding the award of a PhD scholarship.
Keywords
- liquid crystals
- chirality
- spontaneous symmetry breaking
- twist-bend nematic phase
- BEHAVIOR
- LIQUID-CRYSTAL DIMERS
- SYMMETRY-BREAKING
