Computation on radical C59N dimer (C59N)2 by INDO series methods suggests that the introduction of N atom into C60 distorts the cage with the N atom stretching out from the cage, the carbon in the 6-6 bond of C and N has large electron density, where two radicals bind to form dimer (C59N)2 with C2v and C2h symmetry. The C2v isomer is more stable than the C2h and the N atom binds with the connected carbons by single bond. The calculated electronic spectrum is consistent well with that of experiment. The dimer (C59N)2 readily dissociates to the monomer.

Key words: CAGE STRUCTURE, INTERMEDIATE NEGLECT OF DIFFERENTIAL OVERLAP APPROXIMATION (IND, ELECTRONIC SPECTROSCOPY, FULLERENES