Realization of a lateral directional order in nematic and smectic A phases of rodlike molecules by using perfluoroarene–arene interactions

Abstract

In order to realize biaxial mesophases of straight rod-like molecules by introduction of lateral perfluoroarene–arene interactions, non-alkylated rod-like liquid crystalline compounds C₆X₅–COO–C₆Z₄–C₆Z₄–OOC–C₆Y₅, F-BB-F (X = Y = F, Z = H), F-BB-B (X = F, Y = Z = H), B-BB-B (X = Y = Z = H), B-FF-B (X = Y = H, Z = F), F-FF-B (X = F, Y =H, Z = F), and F-FF-F (X = Y = Z = F) were prepared, and their phase transition behaviors were investigated by polarized light optical microscopy (POM) and differential scanning calorimetery (DSC). From the one- and two-dimensional X-ray diffraction (1D- and 2D-XRD) studies of the nematic and smectic A phases of F-BB-F, it was clarified that the smectic A phase had a lateral directional order in the layer and the nematic phase had a cybotactic smectic A structure.