Fig. 5: Crystal structures showing the cationic portions.

a Cage 2c (binuclear), b cage 3a (trinuclear), c cage 4acI (tetranuclear), d cage 5c (pentanuclear), and e cage 6c (hexanuclear) (encapsulated guests, counter-anions, solvents, and hydrogen atoms are excluded for clarity. ORTEP diagram for complexes and suitable crystal structures showing encapsulated guests are available in the Supplementary Figs. 134–143).