Interaction Between an Endohedral N Atom and a C60 Fullerene Cage by Density Functional Theory

Density functional theory calculations were carried out to study the interaction between nitrogen atom and C-60 cage. The endohedral nitrogen atom is spin-polarized with a quartet spin state. The encapsulation of N atom into C-60 cage is exothermic with small incorporation energy of 0.039 eV. Representative patch method was employed to generate the potential energy surface (PES). Comparison of the five representative potential energy curves shows the complicated nature of the nitrogen-fullerene interaction. The computed energy barrier for the penetration of the N atom through a six-membered ring on the fullerene surface is about 19 eV.