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1 Introduction At room temperature, C_(60) takes a crystal structure in which C_(60) molecules arepositioned with their center of mass on an f_∞ (face-centered-cubic) lattice. IndividualC_(60) molecule’s reorientational rapid motion shows up as orientational disorder. At250 K—260 K, the f_∞ lattice system undergoes a first-order transition to a simple cubic(sc) structure with P_a~3 symmetry. Even in the ordered phase, the short-rangedisorder persists to the lower temperature. Recently Shi X. D. et al. reported the studies of the elasticity of C_(60)single crystals. For sublimed f_∞ crystals, Young’s modules had an 8% jump at the
Individual C_ (60) molecule’s reorientational rapid motion shows up. (1) At room temperature, C_ (60) takes a crystal structure in which C_ (60) molecules arepositioned with their center of mass on an f_∞ as orientational disorder. At 250 K-260 K, the f_∞ lattice system undergoes a first-order transition to a simple cubic (sc) structure with P_a ~ 3 symmetry. Even in the ordered phase, the short-rangedisorder persists to the lower temperature . Recently Shi XD et al. Reported the studies of the elasticity of C_ (60) single crystals. For sublimed f_∞ crystals, Young’s modules had an 8% jump at the