STRONTIUM DOPED FULLERITE COMPOUNDS

We report synthesis, structures and properties of strontium intercalat ed fullerite, SrxC60 compounds. This is identified as the only fulleri de system where fcc and bcc phases compete in the same compositional r ange. In the vicinity of x=3, a bcc A15 phase coexists with a fcc phas e with lattice constants 11.140 and 14.144 angstrom, respectively. For Sr6C60, an Im3BAR bcc phase with a0=10.975 Angstrom is observed. This phase becomes superconducting at T=4 K. These structural and electron ic properties, being intermediate to grossly different calcium and bar ium intercalated fullerides, provide a unifying picture of all alkalin e-earth intercalated fullerides.