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Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Synthesis and Spectral Studies of Some Homo Dinuclear Lanthanide(III) Complexes of a Mesogenic Schiff Base
Prem Kumar Shrestha1, Pawan Raj Shakya
1Department of Chemistry, Padma Kanya Multiple Campus, Tribhuvan University. prem24shrestha@gmail.com.
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.
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