Functionalization of [60] fullerene with butadienes: A DFT study

Highlights: ► Reaction of C60 with 2,3-dimethylbutadiene (DMB) is theoretically investigated. ► The HOMO of DMB interacts with the LUMO of C60 via a Diels Alder reaction. ► Work function of C60 is decreased by increasing the number of DMB molecules. ► The reaction may facilitate the field electron emission from C60 surface. - Abstract: We have performed a density functional study on the reaction of C60 fullerene with one to six 2,3-dimethylbutadiene (DMB) molecule(s) which has previously been investigated by experimental researchers. Based on the obtained results, it has been found that (1) the reaction is regioselective, so that the DMB molecule prefers to be adsorbed atop a C-C bond which is shared between two hexagonal rings of C60 (in good agreement with the experimental results) with reaction energy of −0.98 eV; (2) the HOMO of DMB interacts with the LUMO of C60 via a Diels Alder reaction; (3) the energy of reaction and work function of C60 are decreased by increasing the number of adsorbed DMB molecules; (4) the HOMO–LUMO energy gap of C60 is slightly changed upon the reaction; (5) the reaction reduces the potential barrier of the field electron emission of C60 surface.