Supramolecular Chemistry on a Cluster Surface: Fixation/Complexation of Potassium and Ammonium Ions with Crown-Ether-Like Rings

Integrated but separate: A strongly nucleophilic cluster surface allows the selective complexation and separation of ammonium and potassium ions. Six {Mo₄VKO₆} rings with crown-ether-like functionality (see picture; Mo?blue, V?green, K?pink, O?red) present in the holes of the investigated cluster complex integrate six ammonium ions (N?orange, H?yellow).