Lanthanide complexes of a mesogenic Schiff's base having 1,3,4-oxadiazole moiety: Synthesis and characterization

Abstract

A liquid-crystalline Schiff's base (HL) having 1,3,4-oxadiazole moiety with an octyloxy substituent and a series of lanthanide(III) complexes [Ln(LH)3(NO3)3] (LnIII = La, Pr, Nd, Sm, Eu, Tb and Dy; HL = N-(4′-(5-(4″-octyloxyphenyl)-1,3,4-oxadiazol)-2-phenyl)-4‴-octyloxysalicylaldimine) have been synthesized and characterized by FTIR, 1H and 13C{1H} NMR, UV–Vis, fluorescence and Mass spectral techniques. HL exists in zwitter-ionic form in the complexes, binding to the metal through phenolate oxygen; Optical and thermal behavior studies (POM, powder XRD & DSC techniques) indicate SmC and SmX mesophases of HL and non-mesogenic behavior of the complexes. © 2016