Discotic mesomorphism in oxovanadium(IV) complexes possessing four alkyl substituents

Abstract

A series of metal-containing liquid crystals based on β-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.