Calorimetric and spectrophotometric studies of chloro complexes of manganese(II) and cobalt(II) ions in N,N-dimethylformamide

Abstract

The formation of chloro complexes of manganese(II) and cobalt(II) ions has been calorimetrically and spectrophotometrically studied in N,N-dimethyl-formamide (DMF) containing 0.4 mol dm^–3(C₂H₅)₄NClO₄ as a constant ionic medium at 25 °C. Calorimetric data obtained in each system are explained in terms of the formation of [MCl_n]^(2–n)+(n= 1–4 and M = Mn or Co) and their formation constants, enthalpies and entropies were determined. In the cobalt(II) chloro system electronic spectra of individual complexes were also determined. The thermodynamic parameters of formation of the chloro complexes of these metal(II) ions are compared with those of nickel(II), copper(II) and zinc(II) ions.