Liquid crystal phases formed by asymmetric bent-shaped molecules

A few series of asymmetric bent-core compounds with different branches were obtained. Depending on the flexibility and the parity of the unit that joins the central ring with the branches the typical rod-like or banana phases are observed. It is shown that asymmetric materials usually have a broader mesophase range than their symmetric analogues. The rich variety of lamellar and broken-layer columnar phases were found for asymmetric compounds, some of the phases being ferroelectric. Biaxial and uniaxial ferroelectric phases were observed. It has also been proven that some mesophases showing optical bistability under electric fields are unambiguously antiferroelectric.