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The gyroid lattice is prepared in chiral and non‐chiral forms. The chiral gyroid lattice is observed to exhibit temperature‐induced twist with the direction of twist corresponding to the sense of chirality. This effect is a nonclassical effect that cannot occur in classical elasticity or classical thermo‐elasticity but is allowable in Cosserat solids. Poisson's ratio of the gyroid is known to be about 0.3 with minimal dependence on size. In contrast to squeeze–twist coupling in which substantial size effects occur with slender specimens twisting much more than thicker ones, thermal–twist coupling exhibits opposite and less consistent size effects of much smaller magnitude.
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Indication of a twist-grain-boundary-twist-bend phase of flexible core bent-shape chiral dimers
The effect of the molecular chirality of chiral additives on the nanostructure of the twist-bend nematic (N TB ) liquid crystal phase with ambidextrous chirality and nanoscale pitch due to spontaneous symmetry breaking is studied. It is found that the ambidextrous nanoscale pitch of the N TB phase increases by 50% due to 3% chiral additive, and the chiral transfer among the biphenyl groups disappears in the N TB * phase. Most significantly, a twist-grain boundary (TGB) type phase is found at c > 1.5 wt% chiral additive concentrations below the usual N* phase and above the non-CD active N TB * phase. In such a TGB type phase, the adjacent blocks of pseudo-layers of the nanoscale pitch rotate across the grain boundaries.
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- Award ID(s):
- 1659571
- PAR ID:
- 10163825
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 15
- Issue:
- 16
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 3283 to 3290
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c8sm02338g
