DISCOTIC MESOMORPHISM IN OXOVANADIUM(IV) COMPLEXES POSSESSING 4 ALKYL SUBSTITUENTS

A series of metal-containing liquid crystals based on beta-diketonate ligands chelated to a central oxovanadium(IV) metal centre have been prepared. While retaining a common core, the symmetry of the complexes has been varied by using alkyl chains of different lengths. Twenty-eight new complexes are reported, all of which, with the exception of three short-chain derivatives, show optical textures which are characteristic of ordered hexagonal columnar (D(ho)) phases. The identity of the phase has been confirmed by powder diffraction studies. The metal possesses an unpaired electron thereby making the complexes paramagnetic.