The role played by various types of defect in establishing the magnetic properties of C60-based polymers and single-wall C nanotubes was investigated. Comparing the role of C vacancies, and that of substitutional impurity atoms (N, B, O, Si, P, S) in establishing a magnetic ground state, it was found that the impurity atoms promoted spin density delocalization, whereas its localization appeared as one of the primary effects of C vacancies.

Doping and the Unique Role of Vacancies in Promoting the Magnetic Ground State in Carbon Nanotubes and C60 Polymers. A.N.Andriotis, R.M.Sheetz, M.Menon: Physical Review B, 2006, 74[15], 153403 (4pp)