Highly oxygenated fullerene anions C60On− formed by corona discharge ionization in the gas phase

Oxygenated fullerenes anions were produced by a vaporization source equipped with a corona discharge ionizer in the presence of a trace amount of oxygen. In situ mass analysis revealed that the species formulated as C60On− (n⩽30) were formed in the source and that the degree of oxygenation could be altered by the discharge current. Formation of the epoxide structure in the C60On− was suggested by XPS measurements for thin films prepared by deposition of the C60On− beam. The structures and formation processes of higher analogues (C60)mOn− (m=2,3) are briefly discussed.