Investigation of ytterbium fulleride compounds

We have synthesized the ytterbium fulleride compounds YbxC60 (x = 1 - 6) at a range of lower temperature (530 degrees C - 570 degrees C). Except for t he nominal composition Yb3C60 compound, which has been reported in the refe rences, we also obtained a new phase Yb6C60, whose structure is orthorhombi c with space group P2(1)2(1)2 and unit cell parameters a = 21.28 Angstrom, b = 20.13 Angstrom and c = 15.89 Angstrom. The YbxC60 compounds are sensiti ve to oxygen, the samples exposed in air convert to an amorphous phase and Yb2O3 compound.