Fig. 2
Illustration of the solution behaviour of Gd3+ complexes of H4dota. H4dota is an important cyclic ligand ubiquitous in clinical settings. There are four possible stereoisomers for [Gd(dota)]− and interconversion between them is shown. The geometry can be visualised if the donor atoms are considered in planes, with the macrocyclic N4 donors forming one plane (white square), and the acetate O4 donors another (black square). Pairs of enantiomers are diagonally opposite one another. Individual atom charges and coordinated water molecules are omitted for clarity. (Adapted with permission from ref. 55)
