Chirality-Preserving Growth of Helical Filaments in the B4 Phase of Bent-Core Liquid Crystals

Abstract

The growth of helical filaments in the B4 liquid-crystal phase was investigated in mixtures of the bent-core and calamitic mesogens NOBOW and 8CB. Freezing-point depression led to nucleation of the NOBOW B4 phase directly from the isotropic phase in the mixtures, forming large left- and right-handed chiral domains that were easily observed in the microscope. We show that these domains are composed of homochiral helical filaments formed in a nucleation and growth process that starts from a nucleus of arbitrary chirality and continues with chirality-preserving growth of the filaments. A model that coherence of the branched filaments is proposed. This model will help in phase and controlling its growth and morphology for applications, such as medium. accounts for the observed local homochirality and phase providing a better understanding of the nature of the B4 the use of the helical nanophase as a nanoheterogeneous