Thermal conductivity and energetic recoils in UO2 using a many-body potential model
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Date
2014-11-14
Journal Title
Journal ISSN
Volume Title
Publisher
IOP Science
Abstract
Classical molecular dynamics simulations have been performed on uranium dioxide (UO2)
employing a recently developed many-body potential model. Thermal conductivities are
computed for a defect free UO2 lattice and a radiation-damaged, defect containing lattice at
300 K, 1000K and 1500 K. Defects significantly degrade the thermal conductivity of UO2 as
does the presence of amorphous UO2, which has a largely temperature independent thermal
conductivity of ∼1.4Wm−1 K−1. The model yields a pre-melting superionic transition
temperature at 2600 K, very close to the experimental value and the mechanical melting
temperature of 3600 K, slightly lower than those generated with other empirical potentials.
The average threshold displacement energy was calculated to be 37 eV. Although the spatial
extent of a 1 keV U cascade is very similar to those generated with other empirical potentials
and the number of Frenkel pairs generated is close to that from the Basak potential, the
vacancy and interstitial cluster distribution is different. © 2014, IOP Publishing Ltd.
Description
Keywords
Molecules, Nuclear fuels, Amorphous state, Thermal conductivity, Uranium dioxide, Crystal lattices
Citation
Qin, M. J., Cooper, M. W. D., Kuo, E. Y., Rushton, M. J. D., Grimes, R. W., Lumpkin, G. R., & Middleburgh, S. C. (2014). Thermal conductivity and energetic recoils in UO2 using a many-body potential model. Journal of Physics: Condensed Matter, 26(49), 495401. doi:10.1088/0953-8984/26/49/495401