Cryptands and related species

s-block metals are commonly complexed with the macrocyclic cryptands, sepulchrates, and related species to form large, non-interacting cations that are used to stabilize a variety of 

The fulleride dianion has been isolated in the solid state as [K([2.2.2]crypt)]2[Cgo] its structure consists of alternating layers of ordered Cgo anions and [K([2.2.2]crypt)]+ cations. The complete separation of the anions ( 13.77 A) by the cations allows EPR and magnetic susceptibility measurements on the isolated fulleride. 

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