Stability of Coordination Compounds Preparation and Properties
Stability of Coordination Compounds :
→ A coordination compound is formed in solution by the step-wise addition of ligands to a metal ion. The overall formation of complex can be represented as follows:
→ This constant is also called stability constant. The higher stability constant value of the complex indicate more stability of complex.
Factors affecting stability :
→ 1/K value is called dissociation constant of complex.
→ Higher the charged density on the central metal ion, the greater is the stability of its complexes.
→ The higher the electronegativity of central ion, the greater is the stability of its complexes.
→ The more basic a ligand, the greater is the ease with which it can donate its lone pair of electrons and therefore, the greater is the stability of the complexes formed by it. Thus strong bases are good ligands to form stable complexes.
→ The higher the oxidation state of metal, the more stable is the complex.
→ Chelating ligands form more stable complex as compared to monodentate ligands because cyclisation provides stability of complex.