Water exchange on-transition metal ions

The hydration number of the Ln ions has been extensively addressed by various techniques like neutron scattering (121,122), X-ray scattering 

Rate Constants and Activation Parameters for Water Exchange on Lanthanide 

Effect of Non-Leaving Ligand on the Rate Constants and Activation Parameters for Water Exchange on Selected Gd + and Eu + 

The use of the steric crowding to tune the water exchange rate on poly-aminocarboxylate complexes of Gd to its optimum value for MRI contrast 

Water exchange on cationic lanthanide chelates can also be influenced by the nature of the counter-anions (170,171). Anions like halides, sulfate, nitrate, acetate, and fluoroacetate impose different order on the second coordination shell around the chelate by influencing the hydrogen bond network. Anions with a high charge density like CU and S04 can break up the hydrogen bond network between water molecules around the metal center and by that, slow down the water exchange rate of the inner shell water molecule (171). 

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F. Water exchange on first-row transition metal complexes Water exchange on /-transition metal ions... 

Table 1 Parameters for water exchange on transition metal ions. 

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