Isomer Specific Intercalation Chemistry: Potassium Insertion into the D2 and D2d Isomers of C84

Reaction of solids of pure D 2 d and D 2 C 84, as well as mixtures of these isomers, with an excess of potassium produces the cubic phases K 8+ x C 84, with multiple occupancy of the octahedral site by potassium. Analysis of X-ray powder diffraction data reveals that the anions adopt well-defined orientations in the solid, driven by the anion−cation contacts. Electron paramagnetic resonance measurements on the solid fullerides indicate that the electronic properties depend on the particular isomer of C 84 used as host.