Directing Polymorphism in the Helical Nanofilament Phase

Chemistry. 2021 Apr 26;27(24):7108-7113. doi: 10.1002/chem.202005221. Epub 2021 Mar 10.

Abstract

Herein, it is reported that the polymorphism in the helical nanofilament (HNF, B4 ) liquid-crystalline phase depends on the fabrication methods, that is, UV-driven formation and template-assisted self-assembly in the nanoconfined geometry. As a result, uniaxially oriented HNFs with different helical structures were obtained, in which generation of the twisted-ribbon and cylindrical-ribbon polymorphs showed that even the molecular lattice has a different orientation. The detailed structures were directly observed by SEM and grazing-incidence X-ray diffraction with synchrotron radiation. The resultant polymorphs could be used in chiro-optical applications due to the capability for fine control of the helical structures.

Keywords: helical structures; liquid crystals; nanoconfinement; photoalignment; polymorphism.