Spectral properties of Ni(II) complex of a tridentate pyridine-amide ligand with appended ether functionality [n-(2-Methoxyphenyl)picolinamide]: Theoretical and Experimental studies

Abstract

Carboxamide groups due to its biological abundance and significance in the primary structure of proteins/metalloenzymes, has been long investigated as donor functionality in synthetic inorganic coordination chemistry. Spectral studies and their theoretical encounters are gaining enormous importance. Electronic detail structure, along with TD-DFT and FT-IR vibrational frequencies of, [Ni(II)L2], HL = N-(2-methoxyphenyl)picolinamide were studied by DFT calculations and are compared with their experimental counterparts. Nice agreement of these two was obtained. Ni(II) utilizes all possible donor sites of the both the ligands and forms hexadentate complex. Orbitals involved in TD-DFT calculated electronic transitions are highlighted, along with magnetic orbitals and spin-density plots. TD-DFT results and comparison of experimental and calculated vibrational wave numbers are listed in tabular fashion. Optimized geometry reveals possible distortions in the structure. All relevant bond angles and bond lengths have been shown. All calculations were done at B3LYP utilizing TZVP and SVP basis sets.