Novel Green Light Emitting Nondiscoid Liquid Crystalline Zinc(II) Schiff‐Base Complexes

Abstract

Abstract A new series of nondisc‐like Zn II Schiff base complexes of the type [Zn (4‐C n H 2 n +1 O) 2 salophen], n = 14, 16, 18, salophen = N , N ′‐phenylenebis(salicylideneiminato), have been prepared and their mesogenic, photophysical properties investigated. The mesomorphic behaviour of these compounds was studied by differential scanning calorimetry, polarized optical microscopy and X‐ray diffraction (XRD) techniques. The ligands are found to be nonmesogenic, but their complexes exhibited a columnar mesomorphism. The XRD‐study revealed that the molecules are self‐organized into columnar mesophase of the primitive rectangular (Col r ) and/or monoclinic oblique type. At room temperature with 360 nm excitation, all the complexes showed green emission in dichloromethane solution (ca. 507 nm, Φ = 22 %) as well as in the solid state (ca. 516 nm, Φ = 9 %). The DFT calculations were performed using the DMol3 program at BLYP/DNP level to obtain the stable electronic structure of the complex.