Crucial role of molecular curvature for the bend elastic and flexoelectric properties of liquid crystals: mesogenic dimers as a case study

摘要: Using a molecular field theory with atomistic modelling, we provide complete description of the elastic and flexoelectric properties nematic phase formed by liquid crystal dimers which, depending on parity number atoms in spacer, have either bent (odd) or straight (even) average shape. We can then estimate flexoelastic ratio make direct comparison outcome flexoelectro-optic measurements. Our results demonstrate extreme sensitivity bend elasticity flexoelectricity to structure, dramatic differences between even odd dimers. An unusually low constant is predicted for latter; discuss implications this result high response existence Blue Phases stable over wide temperature range, which were both recently claimed