Quantitative estimation of localization errors of 3d transition metal pseudopotentials in diffusion Monte Carlo
The necessarily approximate evaluation of nonlocal pseudopotentials in diffusion Monte Carlo (DMC) introduces localization errors. In this paper, we estimate these errors for two families of nonlocal pseudopotentials for the firstrow transition metal atoms Sc–Zn using an extrapolation scheme and multideterminant wavefunctions. Sensitivities of the error in the DMC energies to the Jastrow factor are used to estimate the quality of two sets of pseudopotentials with respect to locality error reduction. The locality approximation and Tmoves scheme are also compared for accuracy of total energies. After estimating the removal of the locality and Tmoves errors, we present the range of fixednode energies between a single determinant description and a full valence multideterminant complete active space expansion. The results for these pseudopotentials agree with previous findings that the locality approximation is less sensitive to changes in the Jastrow than Tmoves yielding more accurate total energies, however not necessarily more accurate energy differences. For both the locality approximation and Tmoves, we find decreasing Jastrow sensitivity moving left to right across the series Sc–Zn. The recently generated pseudopotentials of Krogel et al. reduce the magnitude of the locality error compared with the pseudopotentials of Burkatzki et al. by an average estimated 40% usingmore »
 Authors:

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 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
 Publication Date:
 Grant/Contract Number:
 AC0500OR22725
 Type:
 Accepted Manuscript
 Journal Name:
 Journal of Chemical Physics
 Additional Journal Information:
 Journal Volume: 147; Journal Issue: 2; Journal ID: ISSN 00219606
 Publisher:
 American Institute of Physics (AIP)
 Research Org:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC22)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Electronic structure calculations; Metalloids; Monte Carlo methods; Wave functions; Matrix theory
 OSTI Identifier:
 1376434
 Alternate Identifier(s):
 OSTI ID: 1368604
Dzubak, Allison L., Krogel, Jaron T., and Reboredo, Fernando A.. Quantitative estimation of localization errors of 3d transition metal pseudopotentials in diffusion Monte Carlo. United States: N. p.,
Web. doi:10.1063/1.4991414.
Dzubak, Allison L., Krogel, Jaron T., & Reboredo, Fernando A.. Quantitative estimation of localization errors of 3d transition metal pseudopotentials in diffusion Monte Carlo. United States. doi:10.1063/1.4991414.
Dzubak, Allison L., Krogel, Jaron T., and Reboredo, Fernando A.. 2017.
"Quantitative estimation of localization errors of 3d transition metal pseudopotentials in diffusion Monte Carlo". United States.
doi:10.1063/1.4991414. https://www.osti.gov/servlets/purl/1376434.
@article{osti_1376434,
title = {Quantitative estimation of localization errors of 3d transition metal pseudopotentials in diffusion Monte Carlo},
author = {Dzubak, Allison L. and Krogel, Jaron T. and Reboredo, Fernando A.},
abstractNote = {The necessarily approximate evaluation of nonlocal pseudopotentials in diffusion Monte Carlo (DMC) introduces localization errors. In this paper, we estimate these errors for two families of nonlocal pseudopotentials for the firstrow transition metal atoms Sc–Zn using an extrapolation scheme and multideterminant wavefunctions. Sensitivities of the error in the DMC energies to the Jastrow factor are used to estimate the quality of two sets of pseudopotentials with respect to locality error reduction. The locality approximation and Tmoves scheme are also compared for accuracy of total energies. After estimating the removal of the locality and Tmoves errors, we present the range of fixednode energies between a single determinant description and a full valence multideterminant complete active space expansion. The results for these pseudopotentials agree with previous findings that the locality approximation is less sensitive to changes in the Jastrow than Tmoves yielding more accurate total energies, however not necessarily more accurate energy differences. For both the locality approximation and Tmoves, we find decreasing Jastrow sensitivity moving left to right across the series Sc–Zn. The recently generated pseudopotentials of Krogel et al. reduce the magnitude of the locality error compared with the pseudopotentials of Burkatzki et al. by an average estimated 40% using the locality approximation. The estimated locality error is equivalent for both sets of pseudopotentials when Tmoves is used. Finally, for the Sc–Zn atomic series with these pseudopotentials, and using up to threebody Jastrow factors, our results suggest that the fixednode error is dominant over the locality error when a single determinant is used.},
doi = {10.1063/1.4991414},
journal = {Journal of Chemical Physics},
number = 2,
volume = 147,
place = {United States},
year = {2017},
month = {7}
}
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