Discotic Liquid Crystales of Organic Metala Complexes (56) : Mesomorphic Properties and Electric Conductivities of Alkyllthio-group-substituted Phthalocyanine Derivatives

Abstract

If a phthalocyanine (Pc) is substituted by non-electro-donating group of alkylthio chains instead of electro-donating group of alkoxy chains, the Q-band may red-shift on the electronic spectra. Hence, The energy difference between HOMO and LUMO levels becomes smaller, so that we can expect better electric conductivity. Accordingly, we synthesised eight long alkylthio-groups-substituted Pc derivatives, octakis(alkylthio)phthalocyanines, and their copper(II) complexes to investigate the mesomorphic properties. Each of them shows a Dh mesophase. Furthermore, we measured the electronic spectra and conductivities and compared with those of the octakis(alkoxy)phthalocyanine derivatives. The influence of the sulfur atoms on these properties will be discussed.