Three sulfate-macrocycle adducts [H6L (HSO4) 4 (SO4)]· H2O (1),[H6L (SO4) 3](2) and [H6L (HSO4) 2Cl4]· 2H2O (3)(where L=[18] aneN6) were crystallized from solutions containing the macrocycle and the appropriate inorganic acids, and [H4L (S2O6) 2]· 2H2O (4) from an aqueous solution of the macrocycle and sodium dithionate. All four structures show that the polyammonium groups on the protonated macrocycle participate in 'co-ordination'or ...