Author: G. C. Paul, S. Bhowmik, J. Biswas, S. Bhowmik, and U. Majumder

DOI: http://doi.org/10.31788/RJC.2026.1919469

In this study, a non-innocent bidentate ligand (H2L) containing Ni(II) complex [Ni(L ISQ)2], (1) was obtained under aerial conditions. The complex was defined by using FT-IR, UV-vis/NIR, 1H-NMR, MASS and X-raycrystallography techniques. The results of the single crystal X-ray diffraction analysis revealed that the Ni(II) complex has a square planar configuration coordinated by two phenolate oxygen atoms and two nitrogen atoms fromthe two H2L-ligands. Spectroscopic analysis also showed that the two H2L ligands coordinated to the Ni(II) ioninthe complex 1, two ortho-substituents -Ph groups were situated -cis to each other with respect to the square planar plane. 1H-NMR spectrum of complex 1 suggested that it is a diamagnetic compound where two unpaired electronsof Ni(II) strongly couple with two one-electron radical ligands. In addition, cyclic voltammetry measurement of thecomplex 1 showed that the complex 1 underwent one two-electron oxidation and two one-electron reductions.

Keywords: Non-innocent Ligand, Ni(II)-Diradical Complex, Galactose Oxidase (GOase), AntiferromagneticCoupling, Diamagnetic Complex, Cyclic Voltammetry.