Experimental and Computational Study of the Thermodynamic Properties of Trivalent Cobalt Schiff Base Complexes with Cyclic Amines

• Main Authors: Sheida Esmaielzadeh, Leila Azimian, Zohreh Zare
• Format: Article
• Language: English
• Published: Slovenian Chemical Society 2016-05-01
• Series: Acta Chimica Slovenica
• Subjects: Cobalt complexes; Unsymmetrical Schiff base; Thermodynamic parameters; computational methods; experimental data.
• Online Access: https://journals.matheo.si/index.php/ACSi/article/view/2335

Some cobalt(III) complexes with a potentially tetradentate unsymmetrical NNOS Schiff base ligand have been synthesized and characterized using IR, 1HNMR, UV-Vis spectroscopy and elemental analysis. The equilibrium constants were measured spectrophotometrically for 1:1 adduct formation of the cobalt(III) complexes with some cyclic amines in acetonitrile as solvent at constant ionic strength (I = 0.1 M NaClO4), and at various temperatures. In addition, the ground state geometries of the complexes were optimized using density functional theory (DFT) at B3LYP/6-311G** level. Binding energy, thermodynamic parameters, structural parameters and electronic structures of complexes are investigated. The theoretical investigations were done for comparing with the experimental results. Our comparison between the computational and experimental results revealed that the cobalt(III) complexation process is spontaneous, exothermic and entropically unfavorable.