Vive la Difference - Mixed-metal Complexation

How the process of sequential complexation of metal ions may be applied to permit coordination to two different metal ions. 

with this unsymmetrical ligand, there are two complexes possible with two different metal ions inserted in different compartments. This simple example is sufficient to illustrate the often vast range of options that becomes available when complicated ligands bind to metal ions. However, not all of these options will be equally probable, as the thermodynamic stability of each of the various options will differ, concepts that we will also deal with further in Chapter 5. 

How the process of choice and selection during complexation of metal ions to an unsymmetrical ligand may lead to two differing MM L forms. 

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