Novel V- and Y-shaped light-emitting liquid crystals with pentafluorinated bistolane-based luminophores

Abstract

Herein, we describe the synthesis of novel light-emitting liquid-crystalline (LC) compounds bearing pentafluorinated bistolane-based luminophores with a V- or a Y-shaped molecular geometry and the evaluation of their LC and photophysical characteristics. The V- or Y-shaped compounds exhibited a unique LC phase and showed photoluminescence (PL) behavior under various circumstances, such as in dilute solution or in the solid state. Notably, PL characteristics were observed even under high-temperature conditions with a crystal (Cr) to LC phase transition, although the PL efficiency ( PL ) was gradually reduced because of thermal molecular motion. Interestingly, PL was found to be completely recovered through the LC - Cr phase transition during the cooling process; the PL characteristics of the V- or Y-shaped compounds were sensitively changed by external thermal stress, giving these compounds the ability to act as thermoresponsive PL sensing materials.