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Title: Large-scale quantum mechanical simulations of high-Z metals

Abstract

High-Z metals constitute a particular challenge for large-scale ab initio calculations, as they require high resolution due to the presence of strongly localized states and require many eigenstates to be computed due to the large number of electrons and need to accurately resolve the Fermi surface. Here, we report recent findings on high-Z materials, using an efficient massively parallel planewave implementation on some of the largest computational architectures currently available. We discuss the particular architectures employed and methodological advances required to harness them effectively. We present a pair-correlation function for U, calculated using quantum molecular dynamics, and discuss relaxations of Pu atoms in the vicinity of defects in aged and alloyed Pu. We find that the self-irradiation associated with aging has a negligible effect on the compressibility of Pu relative to other factors such as alloying.

Authors:
; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
940484
Report Number(s):
UCRL-JRNL-227357
TRN: US0807141
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Computer-Aided Materials Design, vol. 14, N/A, October 12, 2007, pp. 337-347; Journal Volume: 14
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AGING; ATOMS; COMPRESSIBILITY; DEFECTS; EIGENSTATES; ELECTRONS; FERMI LEVEL; IMPLEMENTATION; RESOLUTION; SELF-IRRADIATION

Citation Formats

Yang, L H, Hood, R, Pask, J, and Klepeis, J. Large-scale quantum mechanical simulations of high-Z metals. United States: N. p., 2007. Web. doi:10.1007/s10820-007-9053-1.
Yang, L H, Hood, R, Pask, J, & Klepeis, J. Large-scale quantum mechanical simulations of high-Z metals. United States. doi:10.1007/s10820-007-9053-1.
Yang, L H, Hood, R, Pask, J, and Klepeis, J. Wed . "Large-scale quantum mechanical simulations of high-Z metals". United States. doi:10.1007/s10820-007-9053-1. https://www.osti.gov/servlets/purl/940484.
@article{osti_940484,
title = {Large-scale quantum mechanical simulations of high-Z metals},
author = {Yang, L H and Hood, R and Pask, J and Klepeis, J},
abstractNote = {High-Z metals constitute a particular challenge for large-scale ab initio calculations, as they require high resolution due to the presence of strongly localized states and require many eigenstates to be computed due to the large number of electrons and need to accurately resolve the Fermi surface. Here, we report recent findings on high-Z materials, using an efficient massively parallel planewave implementation on some of the largest computational architectures currently available. We discuss the particular architectures employed and methodological advances required to harness them effectively. We present a pair-correlation function for U, calculated using quantum molecular dynamics, and discuss relaxations of Pu atoms in the vicinity of defects in aged and alloyed Pu. We find that the self-irradiation associated with aging has a negligible effect on the compressibility of Pu relative to other factors such as alloying.},
doi = {10.1007/s10820-007-9053-1},
journal = {Journal of Computer-Aided Materials Design, vol. 14, N/A, October 12, 2007, pp. 337-347},
number = ,
volume = 14,
place = {United States},
year = {Wed Jan 03 00:00:00 EST 2007},
month = {Wed Jan 03 00:00:00 EST 2007}
}
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