Phases for the azafullerides RbxC59N -: art. no. 140301

Using in situ Raman spectroscopy and resistance measurements we demonstrate the existence of a whole family of azafulleride RbxC59N phases. Six phases with x=1,2,3,4,5,6 were identified from a detailed spectroscopic study of the intercalation physics and chemistry. Intriguingly, the most stable phases were observed for RbC59N, Rb2C59N, and Rb4C59N whereas minimum resistance was observed for Rb3C59N. This supports a strong localization of the extra charge density introduced by the nitrogen substitution for all stable phases. These findings together with the observation that the dimer dissociates before RbC59N is formed allowed us to get insight into the effects of cage distortion and chemical doping as well as into the electronic properties of fullerene intercalation compounds.