학술논문

Synthesis and Spectral Studies of Some Homo Dinuclear Lanthanide(III) Complexes of a Mesogenic Schiff Base
Document Type
article
Source
Acta Chimica Slovenica, Vol 68, Iss 4, Pp 904-912 (2021)
Subject
mesogenic schiff-base
lniii complexes
zwitterionic-coordination
mono-capped octahedron
luminescence
Chemistry
QD1-999
Language
English
ISSN
1318-0207
1580-3155
Abstract
A mesogenic Schiff base, N,N’-di(4-decyloxysalicylidene)-1’,8’-diamino-3’,6’-dioxaoctane (H2L) and a series of homo dinuclear lanthanide(III) complexes of the type [Ln2(LH2)3(NO3)4](NO3)2, (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, and Ho) were synthesized and characterized by elemental analysis, mass spectrometry, FTIR, and NMR spectral techniques. The IR and NMR spectral evidences imply bonding of a neutral bidentate H2L species through two phenolate oxygen atoms in its zwitterionic form to LnIII, rendering the overall geometry of the complexes as a seven-coordinate polyhedron – possibly distorted mono-capped octahedron. Differential scanning calorimetry (DSC) and polarizing optical microscopic (POM) studies reveal mesogenic properties (smectic-X, smectic-A and nematic mesophases) in the ligand over a wide range of temperature but none mesomorphism in the LnIII complexes synthesized under this study. Luminescence studies exhibit emissions of H2L and TbIII complex.