A novel fulleride Sm 6 C 60 has been synthesized using high temperature solid state reaction. The Rietveld refinement on high resolution synchrotron Xray powder diffraction data shows that Sm 6 C 60 is isostructural with bodycentered cubic A 6 C 60 (A=K, Ba). Raman spectrum of Sm 6 C 60 is similar to that of Ba 6 C 60 , and the frequencies of two A g modes in Sm 6 C 60 are nearly the same as that of Ba 6 C 60 , suggesting that Sm is divalent and hybridization between C 60 molecules and the Sm atom could exist in Sm 6 C 60 . Resistivity measurement shows a weak T-linear behavior above 180 K, the transport at low temperature is mainly dominated by granular-metal theory.PACS numbers: 71.20. Tx, 67.57.Hi Alkali intercalation into the C 60 host lattice is a successful technique for synthesizing new fullerides.1 Hereafter, an extensive research has been concentrated on the intercalation of a wide variety of atoms or molecules in the C 60 solids. Intercalation of alkali metals in the C 60 solids yields various structural compounds A x C 60 (x=1, 3, 4, 6) with different physical property.2-6 Among these, the superconducting compounds, A 3 C 60 , has attracted considerable interest.3 In this system, the fcc lattice parameter and band filling are tunable by changing the intercalants, T c goes up with increasing lattice parameter, 7 while it rapidly decreases when the nominal valence ( n ) shifts from the half-filling n=3 of t 1u band. 8The study was then extended to the alkali-earth series of AE x C 60 , 9-12 the electrons are introduced by intercalation of alkali-earth metals into the next lowest unoccupied molecular orbital with t 1g symmetry. The superconducting compounds with various structures and critical temperatures were prepared (Ca 5 C 60 , Ba 4 C 60 , Sr 4 C 60 ).9,13 Such tolerance for the C 60 molecular valence in t 1g superconductors makes a striking contrast with the strict constraint for the valence state in the case of t 1u superconductors.The rare-earth metals were also intercalated into the C 60 solids, but only one phase RE 2.75 C 60 (RE=Yb, Sm) was discovered so far.14,15 In this system, the basic structure of 1

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