Synthesis and study of manganese-containing endohedral fullerenes

Fullerenes containing manganese and iron atoms are synthesized in a high-frequency carbonhelium plasma at atmospheric pressure. The electron paramagnetic resonance (EPR) spectrum of the synthesized compound contains not only lines attributed to iron atoms but also the lines of a manganese ion pair with an additional hyperfine structure. The latter lines are assigned to the endohedral complex Mn2@Cn (n > 70). The possible existence of these structures is evaluated from quantum-chemical calculations of the optimum geometry of the endothedral fullerene Mn2@C84 with C2v symmetry. It is found that the manganese atoms are spaced ∼2.72 Å apart at the center of the molecule.