SPECTROSCOPIC AND STRUCTURAL CHARACTERIZATION OF NOVEL METAL–LIGAND COORDINATION COMPLEXES

Abstract

Synthesis and characterization of novel metal-ligand coordination complexes find applications in catalysis, medicinal chemistry and materials science. To achieve the purpose of this research, the macrocyclic ligands, mixed ligands and Schiff bases were utilized in order to form a sequence of compounds through the use of the hydrothermal method, the solvothermal method and also the reflux method. Extensive spectroscopic studies of the same, including UV-Vis, IR, NMR and EPR interpretations, indicated the presence of definite electronic transitions, changes in the coordination of the ligand and paramagnetic qualities, which confirms successful complexation. The particular ligand designs and structural stability were highly applicable with the specific data on the sizes of the unit cell, morphology and coordinate geometries, which have been calculated with the assistance of structural characterization methods, such as the XRD, SEM and single crystal diffraction. Experiments based on biology showed a high degree of antibacterial and antioxidant activity and DNA cleavage; the most effective were the Cu(II) systems, followed by the Ni(II), Co(II) and Zn(II) systems. Both the processes of π-backbonding and ligand field stabilization on the biological functions and electrical behavior were demonstrated at a mechanistic level. The mechanistic explanation of coordination complexes was balanced by spectroscopic and structural data synthesizing, which gave a valid and strong framework of knowledge of structure-function associations. The results obtained in this article indicated the versatility of the metal-ligand complexes that provide material improvement and advances in materials science, medicine and catalytic activity. Another aspect that they highlight is the significance of the coupled characterization methodologies that will direct rational design to design chemistry that is sustainable.