Simulating radiation damage cascades in graphite

Christie, HJ; Robinson, M; Roach, DL; Ross, DK; Suarez-Martinez, I; Marks, NA

Abstract

Molecular dynamics simulation is used to study radiation damage cascades in graphite. High statistical precision is obtained by sampling a wide energy range (100–2500 eV) and a large number of initial directions of the primary knock-on atom. Chemical bonding is described using the Environment Dependent Interaction Potential for carbon. Graphite is found to exhibit a radiation response distinct from metals and oxides primarily due to the absence of a thermal spike which results in point defects and disconnected regions of damage. Other unique attributes include exceedingly short cascade lifetimes and fractal-like atomic trajectories. Unusually for a solid, the binary collision approximation is useful across a wide energy range, and as a consequence residual damage is consistent with the Kinchin–Pease model. The simulations are in agreement with known experimental data and help to clarify substantial uncertainty in the literature regarding the extent of the cascade and the associated damage.

Citation

Christie, H., Robinson, M., Roach, D., Ross, D., Suarez-Martinez, I., & Marks, N. (2015). Simulating radiation damage cascades in graphite. Carbon, 81, 105-114. https://doi.org/10.1016/j.carbon.2014.09.031

• Journal Article Type: Article
• Acceptance Date: Sep 14, 2014
• Online Publication Date: Oct 12, 2014
• Publication Date: Jan 1, 2015
• Deposit Date: Sep 17, 2014
• Publicly Available Date: Apr 5, 2016
• Journal: Carbon
• Print ISSN: 0008-6223
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 81
• Pages: 105-114
• DOI: https://doi.org/10.1016/j.carbon.2014.09.031
• Publisher URL: http://dx.doi.org/10.1016/j.carbon.2014.09.031
• Related Public URLs: http://www.journals.elsevier.com/carbon/
• Additional Information: Funders : Engineering & Physical Sciences Research Council (EPSRC); Projects : Fundamentals of Current and Future uses of Nuclear Graphite; Grant Number: EP/I003312/1