X-ray diffraction study of fullerene soot

The X-my diffraction pattern of pure buckminsterfullerene (C60) is compared to that of exhaustively toluene-extracted fullerene soot. Both show diffraction lines which may be indexed to the 1.420 +/- 0.005 nm cubic lattice, of C60. Additionally, the extracted fullerene soot shows diffraction peaks which may be indexed as the (002), (004), (100), (110), and (112) peaks of a planar benzenoid lattice. The coefficients of thermal expansion for the (311) peak of the C60 lattice and the (002) peak of the planar benzenoid lattice am both 3 x 10(-5)-degrees-C-1, which is the value of the (002) peak of graphite. Both phases of the extracted fullerene soot change on exposure to air at 600-degrees-C: the C60 phase vanishes, and the in-plane component of the benzenoid phase grows.