Archer, A., Foxhall, H.R., Allan, N.L. et al. (5 more authors) (2014) Order parameter and connectivity topology analysis of crystalline ceramics for nuclear waste immobilization. Journal of Physics: Condensed Matter, 26 (48). ISSN 0953-8984
Abstract
We apply bond order and topological methods to the problem of analysing the results of radiation damage cascade simulations in ceramics. Both modified Steinhardt local order and connectivity topology analysis techniques provide results that are both translationally and rotationally invariant and which do not rely on a particular choice of a reference structure. We illustrate the methods with new analyses of molecular dynamics simulations of single cascades in the pyrochlores Gd2Ti2O7 and Gd2Zr2O7 similar to those reported previously (Todorov et al 2006 J. Phys.: Condens. Matter 18 2217). Results from the Steinhardt and topology analyses are consistent, while often providing complementary information, since the Steinhardt parameters are sensitive to changes in angular arrangement even when the overall topological connectivity is fixed. During the highly non-equilibrium conditions at the start of the cascade, both techniques reveal significant localized transient structural changes and variation in the cation connectivity. After a few picoseconds, the connectivity is largely fixed, while the order parameters continue to change. In the zirconate there is a shift to the anion disordered system while in the titanate there is substantial reversion and healing back to the parent pyrochlore structure.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2014 IOP Publishing. This is an author produced version of a paper subsequently published in Journal of Physics: Condensed Matter. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | radiation damage; pyrochlore; Steinhardt order parameters; topological analysis; molecular dynamics simulation; nuclear waste |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 04 May 2015 12:26 |
Last Modified: | 09 Nov 2015 16:02 |
Published Version: | http://dx.doi.org/10.1088/0953-8984/26/48/485011 |
Status: | Published |
Publisher: | Institute of Physics |
Refereed: | Yes |
Identification Number: | 10.1088/0953-8984/26/48/485011 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:85385 |