Molecular dynamics simulation of radiation damage cascades in diamond

Marks, NA; Buchan, JT; Robinson, M; Christie, HJ; Ross, DK; Roach, DL

Abstract

Radiation damage cascades in diamond are studied by molecular dynamics simulations employing the Environment Dependent Interaction Potential for carbon. Primary knock-on atom (PKA) energies up to 2.5 keV are considered and a uniformly distributed set of 25 initial PKA directions provide robust statistics. The simulations reveal the atomistic origins of radiation-resistance in diamond and provide a comprehensive computational analysis of cascade evolution and dynamics. As for the case of graphite, the atomic trajectories are found to have a fractal-like character, thermal spikes are absent and only isolated point defects are generated. Quantitative analysis shows that the instantaneous maximum kinetic energy decays exponentially with time, and that the timescale of the ballistic phase has a power-law dependence on PKA energy. Defect recombination is efficient and independent of PKA energy, with only 50% of displacements resulting in defects, superior to graphite where the same quantity is nearly 75%.

Citation

Marks, N., Buchan, J., Robinson, M., Christie, H., Ross, D., & Roach, D. (2015). Molecular dynamics simulation of radiation damage cascades in diamond. [Dataset]

• Publication Date: Jan 1, 2015
• Deposit Date: Aug 20, 2015
• Publisher URL: https://doi.org/10.17866/rd.salford.c.4864299.v1
• Related Public URLs: http://dx.doi.org/10.1063/1.4922457; http://scitation.aip.org/content/aip/journal/jap;jsessionid=1tf003oqhssgk.x-aip-live-06
• Type of Data: Plain-text ASCII. Molecular dynamics trajectories are in Cartesian (XYZ) format with gzip compression applied. Distances in Angstroms and employing periodic boundary conditions. Simulations performed using the Environment Dependent Interaction Potential f
• Additional Information: Additional Information : Published. Journal of Applied Physics 117, 245901 (2015); Access Information : Details of the data are available through the Official URL. The data are Plain-text ASCII. Molecular dynamics trajectories are in Cartesian (XYZ) format with gzip compression applied. Distances in Angstroms and employing periodic boundary conditions. Simulations performed using the Environment Dependent Interaction Potential for carbon (http://dx.doi.org/10.1103/PhysRevB.63.035401); Funders : Pawsey Supercomputing Centre with funding from the Australian Government and the Government of Western Australia;Engineering and Physical Sciences Research Council (EPSRC);Australian Research Council; Grant Number: EP/I003223/1; Grant Number: FT120100924