Stepwise Formation of Metal Complexes in Non-Aqueous Solvents
Stepwise complex formation in non-aqueous solvents is a much less frequent phenomena than in aqueous solutions, where the stepwise substitution of water molecules by mono-dentate ligands is a common process with hydrated metal ions. Experience from work with aqueous solutions demonstrates two essential factors for a study of stepwise complex formation: a) effective solvation, which dissociates the metalsalt MXm into M(H2O)n + and mX , b) the possibility to vary the central ion and the ligand concentration over a wide range. These two conditions are not so easy to realize in non-aqueous solvents, and this may be one reason why most stability constants have been determined in aqueous solutions. However, the knowledge of a metalligand system will be more complete if it is studied in several different media (states). the stability of a complex in water, may, for example, be due to a mixed ligand stabilization of a complex ML4 (H2O)2 , which is built into the water lattice. Two examples are taken here to illustrate this point and to demonstrate some techniques of studying stepwise complex formation in non aqueous solvents. Further material will be delivered at the conference.
KeywordsStability Constant Effective Solvation Aqueous Solvent Inert Solvent Stepwise Formation
Unable to display preview. Download preview PDF.