A mathematical evaluation of the shape factor of aggregates formed by amphiphilic compounds in an aqueous medium has been carried out on the basis of dynamic light scattering data for self-associating systems based on metallocomplexes of alkylated derivatives of 1,4-diazabicyclo[2.2.2]octane with Ag(I) and Gd(III) nitrates, a ligand, and a ligand–inorganic salt mixture. Micellar and vesicular approximations have been used. A relationship between the shape factor and the parameters of the water pool of an aggregate has been shown for vesicular systems.