Nematic twist-bend phase with nanoscale modulation of molecular orientation
Abstract
A state of matter in which molecules show a long-range orientational order and no positional order is called a nematic liquid crystal. The best known and most widely used (for example, in modern displays) is the uniaxial nematic, with the rod-like molecules aligned along a single axis, called the director. When the molecules are chiral, the director twists in space, drawing a right-angle helicoid and remaining perpendicular to the helix axis; the structure is called a chiral nematic. In this work, using transmission electron and optical microscopy, we experimentally demonstrate a new nematic order, formed by achiral molecules, in which the director follows an oblique helicoid, maintaining a constant oblique angle with the helix axis and experiencing twist and bend. The oblique helicoids have a nanoscale pitch. The new twist-bend nematic represents a structural link between the uniaxial nematic (no tilt) and a chiral nematic (helicoids with right-angle tilt).
Keywords
Cite
@article{arxiv.1309.1452,
title = {Nematic twist-bend phase with nanoscale modulation of molecular orientation},
author = {Volodymyr Borshch and Young-Ki Kim and Jie Xiang and Min Gao and Antal Jákli and Vitaly P. Panov and Jagdish K. Vij and Corrie T. Imrie and Maria-Gabriela Tamba and Georg H. Mehl and Oleg D. Lavrentovich},
journal= {arXiv preprint arXiv:1309.1452},
year = {2014}
}
Comments
31 pages: 8 Figures and Supplementary Information with 3 Figures