2017/10/02 by Michael R. Tuchband, Daniel A. Paterson, Tuchband, Michael R. +29
Engineering · Materials Science · Physics and Astronomy · #Advanced Materials and Mechanics #Block Copolymer Self-Assembly #FOS: Physical sciences #Liquid Crystal Research Advancements #Soft Condensed Matter (cond-mat.soft) #cond-mat.soft
paper · pdf · doi:10.48550/arxiv.1710.00922
supplemental information included
openalex publication_date 2017/10/02 · arxiv created 2018/02/19 · arxiv updated 2018/02/21 · openalex created_date 2022/10/06 · openalex updated_date 2026/07/28
We synthesized the liquid crystal dimer and trimer members of a series of flexible linear oligomers and characterized their microscopic and nanoscopic properties using resonant soft x-ray scattering and a number of other experimental techniques. On the microscopic scale, the twist-bend phases of the dimer and trimer appear essentially identical. However, while the liquid crystal dimer exhibits a temperature-dependent variation of its twist-bend helical pitch varying from 100 - 170 Å on heating, the trimer exhibits an essentially temperature-independent pitch of 66 Å, significantly shorter than those reported for other twist-bend forming materials in the literature. We attribute this to a specific combination of intrinsic conformational bend of the trimer molecules and a sterically favorable intercalation of the trimers over a commensurate fraction (two-thirds) of the molecular length. We develop a geometric model of the twist-bend phase for these materials with the molecules arranging into helical chain structures, and we fully determine their respective geometric parameters.