Synthesis, Characterization, and Computational Studies of Metal(II) Complexes Derived from β-diketone and Para-aminobenzoic Acid

Some metal(II) mixed-ligand complexes of Mn, Fe, Co, Ni, Cu, and Zn, derived from 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Tf) and para-aminobenzoic acid (Pa) were synthesized. Spectroscopic characterization was carried which includes infrared (IR) and electronic spectra (solid reflectance) measurements. Melting points, magnetic moments at room temperature, solubility, conductivity and percentage metal were also determined. The infrared spectra measurements suggest that the metal atoms coordinated to both ligands, Tf and Pa through the O-4, chromophores. The magnetic moments, percentage metal analysis, and electronic spectra measurements were used to confirm the octahedral geometry of Co(II), Ni(II) and the four-coordinate (tetrahedral/square-planar) complexes (Mn(II), Fe(II), and Cu(II)). The non-electrolytic nature of all the synthesized complexes was shown by conductivity measurements. The density functional theory calculations for all the metal complexes also support experimental results. Mn(II) and Fe(II) complexes had lower energy gaps, indicating higher reactivity compared to others. [GRAPHICS] .