Paramagnetic chiral mesophases of Shiff's base complexes of transition metals

Copper(II), nickel(II) and oxovanadium(IV) complexes of 4-(4-heptyloxybenzoyloxy)-N-(S)-2-methylbutylsalicylaldimine, as well as the parent ligand, were studied by optical and DSC methods. For the first two complexes, there exist between a tightly twisted chiral nematic phase and the isotropic liquid either some blue phases or novel-type amorphous phases, with their temperature ranges depending significantly on the metal centre. For the third complex, direct isotropization takes place.