Thiobiuret based Ni(II) and Co(III) complexes: Synthesis, molecular structures and DFT studies

Abstract

Synthesis, molecular structures and DFT investigations of two new complexes of Ni(II) and Co(III) with (Z)-3-(3,3-dimethylbutanoyl)-1,1-diethyl-2-thiobiuret ligand are reported. Characterization of these complexes was achieved by spectroanalytical techniques (FT-IR, UV–vis and 1H NMR), and the structures were finally confirmed unequivocally by single crystal X-ray diffraction analysis. The obtained data of UV–vis, FT-IR and 1HNMR were compared with the literature values which satisfactorily confirmed the synthesis of ligand and their complexes. X-ray studies revealed the square planar and octahedral geometry of both Ni(II) and Co(III) complexes, respectively. Density functional theory (DFT) studies were performed to compare the theoretical results with experimental (X-ray as well as spectroanalytical) results, and good correlation was observed. Frontier molecular orbitals (FMOs) and molecular electrostatic potential (MEP) analyses revealed the reactivity and charge distribution in both complexes.