Synthesis of Liquid crystals with terminal polar groups and study their mesomorphic and spectroscopic properties

Abstract

Synthesis new Schiffs bases substituted with polar groups CI . Br , F , N02, CH3 , OCH3 , COCH3 in para position or aniline moiety, and derived Cu ( II ) complex from the Schiff base which substituted with COCH3. The Schiffs bases substituent with CH3 , OCH3 exhibited Nematic phase but the other Schiff bases and Cu ( II ) complex exhibited Smectic phase ( Sc ) only. Molecular complexes of Cu (II) complex with various nitrogen bases were studied spectrophotometrically in benzene solvent at different temperatures. These entire complex show a new broad charge transfer band in the visible region of the electromagnetic spectrum. All the donors are known to form I: I complex with the acceptor and their stoichiometry was unaffected by the variation of temperature over a small interval. The thermodynamic and spectroscopic parameters were evaluated. The order of donor strength followed the sequence: Butyl amine> 4 - methyl pyridine > N,N – dimethyl aniline.