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Early stages of radiation damage in graphite and carbon nanostructures: A first-principles molecular dynamics study

Oleg V. Yazyev·Ivano Tavernelli·Ursula Rothlisberger·Lothar Helm
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Abstract

Understanding radiation-induced defect formation in carbon materials is crucial for nuclear technology and for the manufacturing of nanostructures with desired properties. Using first principles molecular dynamics, we perform a systematic study of the non-equilibrium processes of radiation damage in graphite. Our study reveals a rich variety of defect structures (vacancies, interstitials, intimate interstitial-vacancy pairs, and in-plane topological defects) with formation energies of 5--15 eV. We clarify the mechanisms underlying their creation and find unexpected preferences for particular structures. Possibilities of controlled defect-assisted engineering of nanostructures are analyzed. In particular, we conclude that the selective creation of two distinct low-energy intimate Frenkel pair defects can be achieved by using a 90--110 keV electron beam irradiation.

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Oleg V. Yazyev, Ivano Tavernelli, Ursula Rothlisberger, Lothar Helm. 2007-03-25. Early stages of radiation damage in graphite and carbon nanostructures: A first-principles molecular dynamics study. https://doi.org/10.1103/physrevb.75.115418

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