2020/08/18 by Bing-Xiang Li, Bingxiang Li, Li, Bing-Xiang +19
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Advanced Materials and Mechanics #Bent molecular geometry #Birefringence #Chemical Physics (physics.chem-ph) #Chemistry #Composite material #Condensed matter physics #Core (optical fiber) #Crystal structure #Crystallography #Dielectric #Diffraction #FOS: Physical sciences #Liquid Crystal Research Advancements #Liquid crystal #Materials science #Molecule #Optics #Phase (matter) #Photonic Crystals and Applications #Physics #Soft Condensed Matter (cond-mat.soft) #Tetragonal crystal system #cond-mat.soft #physics.chem-ph
paper · pdf · doi:10.48550/arxiv.2008.07818
published in arXiv (Cornell University) (Cornell University) · 35 pages, 18 figures
arxiv created 2020/08/18 · openalex publication_date 2020/08/18 · arxiv updated 2020/08/19 · openalex created_date 2020/08/24 · openalex updated_date 2026/08/08
Liquid crystals formed by acute-angle bent-core (ABC) molecules with a 1,7 naphthalene central core show an intriguing phase behavior with the nematic phase accompanied by poorly understood additional phases. In this work, we characterize the physical properties of an ABC material, such as birefringence, dielectric permittivities, elastic constants, and surface alignment, and present X-ray diffraction and transmission electron microscopy studies of their ordering. The ABC molecular shape resembling the letter λ yields a very small splay elastic constant in the uniaxial nematic phase and results in the formation of a tetragonal positionally ordered columnar phase consisting of molecular columns with a uniform uniaxial director that can be bent but not splayed.