Luminous Nematic Threads: Single-Component Liquid Crystal Self-Assembles into Fluorescent Fibers

Abstract

We report the synthesis and mesomorphic properties of two new series of single-component liquid crystal dimers, prepared by N-alkylation of 1,4-phenylenedimethanamine with two 4-cyanobiphenyl units linked by aliphatic spacers (n=4-10). Polarizing optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) reveal that most dimers exhibit nematic phases, with several displaying stable super-cooled room-temperature mesophases. Rare ±1 nematic defects in viscous thick films spontaneously drive fluorescent fiber formation (72.1% quantum yield), with Schlieren patterns mapping dimer elasticity/viscosity. This design and study provides key insights into fabricating luminous nematic fibers, paving the way for further exploration of their applications in optoelectronic devices.