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Title: Atomistic material behavior at extreme pressures

Abstract

Computer simulations are routinely performed to model the response of materials to extreme environments, such as neutron (or ion) irradiation. The latter involves high-energy collisions from which a recoiling atom creates a so-called atomic displacement cascade. These cascades involve coordinated motion of atoms in the form of supersonic shockwaves. These shockwaves are characterized by local atomic pressures >15 GPa and interatomic distances <2 Å. Similar pressures and interatomic distances are observed in other extreme environment, including short-pulse laser ablation, high-impact ballistic collisions and diamond anvil cells. Displacement cascade simulations using four different force fields, with initial kinetic energies ranging from 1 to 40 keV, show that there is a direct relationship between these high-pressure states and stable defect production. An important shortcoming in the modeling of interatomic interactions at these short distances, which in turn determines final defect production, is brought to light.

Authors:
 [1];  [1];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1324074
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
npj Computational Materials
Additional Journal Information:
Journal Volume: 2; Journal ID: ISSN 2057-3960
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Atomistic models; Computational methods

Citation Formats

Beland, Laurent K., Osetskiy, Yury N., and Stoller, Roger E.. Atomistic material behavior at extreme pressures. United States: N. p., 2016. Web. doi:10.1038/npjcompumats.2016.7.
Beland, Laurent K., Osetskiy, Yury N., & Stoller, Roger E.. Atomistic material behavior at extreme pressures. United States. doi:10.1038/npjcompumats.2016.7.
Beland, Laurent K., Osetskiy, Yury N., and Stoller, Roger E.. Fri . "Atomistic material behavior at extreme pressures". United States. doi:10.1038/npjcompumats.2016.7. https://www.osti.gov/servlets/purl/1324074.
@article{osti_1324074,
title = {Atomistic material behavior at extreme pressures},
author = {Beland, Laurent K. and Osetskiy, Yury N. and Stoller, Roger E.},
abstractNote = {Computer simulations are routinely performed to model the response of materials to extreme environments, such as neutron (or ion) irradiation. The latter involves high-energy collisions from which a recoiling atom creates a so-called atomic displacement cascade. These cascades involve coordinated motion of atoms in the form of supersonic shockwaves. These shockwaves are characterized by local atomic pressures >15 GPa and interatomic distances <2 Å. Similar pressures and interatomic distances are observed in other extreme environment, including short-pulse laser ablation, high-impact ballistic collisions and diamond anvil cells. Displacement cascade simulations using four different force fields, with initial kinetic energies ranging from 1 to 40 keV, show that there is a direct relationship between these high-pressure states and stable defect production. An important shortcoming in the modeling of interatomic interactions at these short distances, which in turn determines final defect production, is brought to light.},
doi = {10.1038/npjcompumats.2016.7},
journal = {npj Computational Materials},
number = ,
volume = 2,
place = {United States},
year = {Fri Aug 05 00:00:00 EDT 2016},
month = {Fri Aug 05 00:00:00 EDT 2016}
}

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