Structural characterization of the C_60[C(COOC_2H_5)_2] whiskers prepared by the liquid–liquid interfacial precipitation method

Fine whiskers of a C_60 derivative, i.e., C_60 monosubstituted by ethyl ester of malonic acid, C_60[C(COOC_2H_5)_2], were fabricated for the first time using a system of toluene with concentrated C_60[C(COOC_2H_5)_2] and isopropyl alcohol. The center-to-center distance of C_60[C(COOC_2H_5)_2] molecules along the close-packed direction of the C_60[C(COOC_2H_5)_2] whiskers was in the same range as that of the C_60 nanowhiskers prepared by the same method. The C_60[C(COOC_2H_5)_2] whiskers were assumed to take body-centered tetragonal or hexagonal close-packed crystal structures. The C_60[C(COOC_2H_5)_2] whiskers showed a high density of stacking faults. The C_60[C(COOC_2H_5)_2] whiskers with the growth direction different from the C_60 whiskers were observed.