The study of dynamics of point defects in graphite was crucial for understanding the evolution of defect-induced ferromagnetism in 12C+ irradiated graphite. In this work, first-principles calculations were performed in order to explore the diffusion and coalescence of vacancies and interstitials in graphite. Different kinds of point defects, such as monovacancy, divacancy, 'bridge' and 'spiro' interstitials were considered using non-interacting and interacting models (table 15). The energetics, the diffusion paths, and the migration energies of these defects and the energy barriers for the reaction between these defects were predicted. The annealing behaviors of point defects and related ferromagnetism found in 12C+ irradiated graphite were discussed.

Diffusion and Coalescence of Vacancies and Interstitials in Graphite: a First-Principles Study. Zhang, H., Zhao, M., Yang, X., Xia, H., Liu, X., Xia, Y.: Diamond and Related Materials, 2010, 19[10], 1240-4

Table 15

Formation and migration energies of

vacancies and interstitials in graphite