ENAMINOKETONES AS NEW HYDROGEN-BONDED LIQUID-CRYSTALS

The relation between molecular structure of enaminoketone derivatives and their mesomorphic properties is discussed. It has been observed th at the electron accepting terminal groups (F,Cl,Br,CN) promote formati on of orthogonal phases while strongly electron donating groups (OCnH2 n+1) favour tilted phases. Among the synthesised compounds, materials useful for structural studies of two dimensional (2D) melting in ortho gonal, as well as the tilted systems, were found. It has been determin ed that the heat effects in the melting process from crystalline smect ic into liquid-like smectic, through the hexatic state, are correlated to the density changes.