Stability and molecular modelling of cobalt (II) and nickel (II) with polydentate Schiff base
Résumé
The cobalt (II) and nickel (II) complexes with H 3 L polydentate Schiff base (N[(1E) phenylmethylene N{2[2(2 {hydroxyphenylmethylene] amino} ethyl) imidazolidin-1-yl} ethylamine) were identified in water-ethanol medium (90%/10%) at 25°C at a constant ionic strength of 0.2 M by potentiometry. Sirko program was used in order to determine the number and the stability constants of the complex species formed in aqueous solution. Totally deprotonated species [ML]and protonated mononuclear species [MHL] (L= deprotonated polydentate ligand) were found in the Co(II)-H 3 L and Ni(II)-H 3 L systems. This study is completed by molecular modelling. The minimized steric energy and optimized geometry of Co(II) and Ni(II) complexes were obtained using the computer EMO program. Indeed a direct correlation was obtained between steric energies of the complexes and their formation constants.
Domaines
Chimie
Origine : Accord explicite pour ce dépôt