Slow evaporation of a mixture of organic solvents containing meso-tetraphenylporphyrinato-magnesium(II), MgTPP and N -methyl-2-(4'- N -imidazolylphenyl)-fulleropyrrolidine, C ₆₀ Im yielded, air stable, dark purple crystals. Determination of the structure by single crystal X-ray diffraction revealed two forms of slightly varying self-assembled via axial coordination MgTPP : C ₆₀ Im dyad. The Mg - N distance of the newly formed coordinate bond was found to be 2.131 Å which was close to the porphyrin ring Mg - N bond distances. The edge-to-edge distances were found to be 9.024 and 9.269 Å, respectively, for the two structure forms. The center-to-center distance between the magnesium and fullerene was 13.296 Å irrespective of the structural forms. Additional intermolecular type interactions between the magnesium porphyrin and fullerene entities that are not axially coordinated were also observed. DFT calculations performed at the B3LYP/3-21G(*) level on the fullerene and porphyrin segments suggested that the charge transfer type π–π interactions are primarily responsible for the intermolecular association of the presently studied donor-acceptor dyad.