TY - JOUR
T1 - The Chiral Twist-Bend Nematic Phase (N*TB)
AU - Walker, Rebecca
AU - Pociecha, Damian
AU - Storey, John Mervyn David
AU - Gorecka, Ewa
AU - Imrie, Corrie Thomas
N1 - Acknowledgements
E.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.
PY - 2019/10/17
Y1 - 2019/10/17
N2 - 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.
AB - 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.
KW - liquid crystals
KW - chirality
KW - spontaneous symmetry breaking
KW - twist-bend nematic phase
KW - BEHAVIOR
KW - LIQUID-CRYSTAL DIMERS
KW - SYMMETRY-BREAKING
UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/chem.201903014
UR - http://www.mendeley.com/research/chiral-twistbend-nematic-phase-ntb
UR - http://dx.doi.org/10.1002/chem.201903014
UR - http://www.scopus.com/inward/record.url?scp=85071863554&partnerID=8YFLogxK
U2 - 10.1002/chem.201903014
DO - 10.1002/chem.201903014
M3 - Article
C2 - 31322779
VL - 25
SP - 13329
EP - 13335
JO - Chemistry : a European Journal
JF - Chemistry : a European Journal
SN - 0947-6539
IS - 58
ER -
