Ligand exchange can proceed through different mechanisms, primarily associative, dissociative, and interchange mechanisms:
1. Associative Mechanism (A): An incoming ligand attaches to the metal center before the departure of the existing ligand, forming an intermediate complex with increased coordination number. 2. Dissociative Mechanism (D): The existing ligand leaves the metal center, creating a coordination site that the incoming ligand then occupies. 3. Interchange Mechanism (I): A simultaneous exchange where the incoming ligand and the outgoing ligand are in a transition state without forming a stable intermediate.
