Abstract: “The complex interaction studies involved complex formation reactions between 14-membered tetraaza macrocycle ligand and Cu2+ and Fe2+ metal cations in methanol-water (MeOH-H2O) binary mixtures at different temperatures by applying conductometric method. These are very important due to their role in some analytical applications such as molecular recognition and biological transportation mechanisms. In all cases, the Log Kf of 1:1 formed complexes between ligand and cations were obtained by fitting the molar conductivity curves using the Genplot computer program. The values of thermodynamic parameters, standard enthalpy (∆H) and standard entropy (∆S) for the complexes were obtained from the temperature dependence of the stability constants using the van’t Hoff plots. Complexations in every case were found to be entropy stabilized, and the selectivity order of all complexes changes as well as the changes in composition of the solvent mixtures.”

Keywords: conductometric method, 14-membered tetraaza macrocycle ligand, thermodynamic study.