Quantum Mechanical Characterization of Mixed-Ligand Complex of Co(II) Dimethylglyoxime

I.A. Adejoro, O.O. Adeboye, B. Akintoye and O.F. Akinyele

Non-electrolyte mixed-ligand complex of the general formula [Co(Hdmg)B], where Hdmg = dimethylgloximato monoanion, B = 2-aminophenol(2-aph), diethylamine (dea) or malonic acid (MOH) has been synthesized and characterized. The aim of this study is to use quantum mechanical approach to elucidate the geometries and thermodynamic parameters, vibrational frequencies, dipole moments and HOMO-LUMO band gaps of the complex with different substituents were carried out. These properties were obtained using the PM3 and DFT with B3LYP at 6-31G* level. The uv/visble spectrum of CoHdmg(dea)₂ showed well resolved absorption bands at 467, 485 nm, these transitions are attributed to metal-ligand charge transfer transitions while the band at 535 nm is assigned to d-d transition within the metal.The uv/visible spectrum of CoHdmg(2aph) presents three distinct bands at 497, 650 nm attributed to metal-ligand charge transition while the band at 650 nm may account for d-d transition with d-orbital of the meatal ion. Likewise the three prominent bands in the uv/visible spectrum of CoHdgm(MO) at 451, 463 nm are metal-ligand charge transfer transitions while the band at 570 nm is attributed to the d-d transition within the d-orbitals of the metal ion It was observed that the calculated data are in good agreement with experimental data.

View Fulltext Back