Iterated Moiré maps and braiding of chiral polymer crystals.
نویسندگان
چکیده
In the hexagonal columnar phase of chiral polymers a bias towards cholesteric twist competes with braiding along an average direction. When the chirality is strong, screw dislocations proliferate, leading to either a tilt grain boundary phase or a new “moiré state” with twisted bond order. Polymer trajectories in the plane perpendicular to their average direction are described by iterated moiré maps of remarkable complexity.
منابع مشابه
Defects in chiral columnar phases: Tilt-grain boundaries and iterated moiré maps.
Biomolecules are often very long with a definite chirality. DNA, xanthan and poly-γbenzyl-glutamate (PBLG) can all form columnar crystalline phases. The chirality, however, competes with the tendency for crystalline order. For chiral polymers, there are two sorts of chirality: the first describes the usual cholesteric-like twist of the local director around a pitch axis, while the second favors...
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ورودعنوان ژورنال:
- Physical review letters
دوره 74 13 شماره
صفحات -
تاریخ انتشار 1995