The bonding of H in Zr under strain
File(s)
Published version
Author(s)
Smutna, J
Wenman, MR
Horsfield, AP
Burr, PA
Type
Journal Article
Abstract
Accurate computer simulation is important for understanding the role of irradiation-induced defects in zirconium alloys found in nuclear reactors. Of particular interest is the distribution and trapping of hydrogen, and the formation of zirconium hydride. These simulations require an accurate representation of Zr-H bonding in order to predict the behaviour of H around atomic-scale defects, dislocation lines, and dislocation loops. Here we explore the bonding of H in Zr under strain, how well it is represented by state-of-the-art Embedded Atom Method (EAM) potentials, and what physics is needed for an accurate representation in a Linear Combination of Atomic Orbitals (LCAO) Density Functional Theory (DFT) framework. For H in dilute solution under hydrostatic strain in the range -10% to +10%, solution energies and Zr-H bond lengths computed using EAM potentials are found to be in poor agreement with plane-wave DFT results. We note that the bond lengths are in a poor agreement even in equilibrium. LCAO basis sets are used to explore the importance of electron distribution around H atoms, and the transfer of electrons between H and Zr. The electron distribution around H atoms is found to be important to the explanation of the difference between octahedral and tetrahedral interstitial sites for H, with H in a tetrahedral site having very similar bonding to H in zirconium hydrides. The interatomic electron transfer has a smaller impact but is needed for maximum accuracy.
Date Issued
2023-01
Date Acceptance
2022-11-03
Citation
Journal of Nuclear Materials, 2023, 573, pp.1-12
ISSN
0022-3115
Publisher
Elsevier BV
Start Page
1
End Page
12
Journal / Book Title
Journal of Nuclear Materials
Volume
573
Copyright Statement
© 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
License URL
Identifier
https://www.sciencedirect.com/science/article/pii/S0022311522006031?via%3Dihub
Publication Status
Published
Article Number
154124
Date Publish Online
2022-11-04