Linear enthalpy relationships. Zinc(II), cobalt(II), nickel(II), copper(II) -bipyridyl/phenanthrolme-N-( meta-substituted phenyl) iminodiacetic acid ternary systems

Abstract

According to a method reported earlier (Chen et al., J. Inorg. Chem., 1 (1985) 13) the heat of protonation of the ligands (N-( meta-substituted phenyl) iminodiacetic acids) ( m-RC 6H 4N(COOH) 2, R = CH 3, CH 3O, H, Cl), the heat formation of complex compounds formed from these ligands with Cu(II), and the heats of formation of ternary complex compounds formed from Zn(II), Co(II), Ni(II), Cu(II) with 2,2'-bipyridyl or 1,10-phenanthroline and N-( meta-substituted phenyl) iminodiacetic acids have been determined by a calorimetric method. The results showed the existence of linear enthalpy relationships between the heats of formation of these complex compounds and the heats of protonation of ligands conforming to the equation Δ H M = Q − βΔ H HL.