C60 bearing ethylene moieties

► The regioselectivity of C60 is studied based on vibronic coupling density (VCD). ► Since the LUMOs of C60 are delocalized throughout the molecule, the frontier orbital theory encounters difficulty to predict its reactive sites. ► On the other hand, the VCD analysis clearly illustrate the existence of ethylene moieties in C60. ► The VCD for the reaction mode can be regarded as a reactivity index.