⁸⁷Rb NMR investigations on binary and ternary fullerene compounds: Rb₃C₆₀, K₂RbC₆₀ and Rb₂CsC₆₀

Results of13C MAS NMR and87Rb NMR measurements on Rb3C60, K2RbC60 and Rb2CsC60 are presented. The87Rb NMR spectra show generally the same characteristics as already reported by other authors. For the ternary compound the degree of site preferential order of the alkali metal ions agrees with the analysis of X-ray absorption data. Furthermore, in the room temperature87Rb NMR spectra of all samples an additional broadened line is detected indicating that at least for the samples prepared from sublimed C60 a considerable amount of the Rb ions is located on sites with symmetry lower than cubic