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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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9 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

High-throughput determination of Hubbard $U$ and Hund $J$ values for transition metal oxides via the linear response formalism

DFT+U provides a convenient, cost-effective correction for the self-interaction error (SIE) that arises when describing correlated electronic states using conventional approximate density functional theory (DFT). The success of a DFT+U(+J) calculation hinges on the accurate determination of its Hubbard U and Hund J parameters, and the linear response (LR) methodology has proven to be computationally effective and accurate for calculating these parameters. This study provides a high-throughput computational analysis of the U and J values for transition metal d-electron states in a representative set of over 1000 magnetic transition metal oxides (TMOs), providing a frame of reference for researchers who use DFT+U to study transition metal oxides. In order to perform this high-throughput study, an ATOMATE workflow is developed for calculating U and J values automatically on massively parallel supercomputing architectures. Here, to demonstrate an application of this workflow, the spin-canting magnetic structure and unit cell parameters of the multiferroic olivine LiNiPO4 are calculated using the computed Hubbard U and Hund J values for Ni-d and O-p states, and are compared with experiment. Both the Ni-d U and J corrections have a strong effect on the Ni-moment canting angle. Additionally, including a O-pU value results in a significantly improved agreement between the computed lattice parameters and experiment

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PuO2 by Materials Project

PuO2 is Fluorite structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Pu4+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pu–O bond lengths are 2.33 Å. O2- is bonded to four equivalent Pu4+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pu2O3 by Materials Project

Pu2O3 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Pu3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pu–O bond distances ranging from 2.28–2.61 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to six equivalent Pu3+ atoms to form OPu6 octahedra that share corners with twelve equivalent OPu4 tetrahedra, edges with six equivalent OPu6 octahedra, and edges with six equivalent OPu4 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Pu3+ atoms to form OPu4 tetrahedra that share corners with six equivalent OPu6 octahedra, corners with six equivalent OPu4 tetrahedra, edges with three equivalent OPu6 octahedra, and edges with three equivalent OPu4 tetrahedra. The corner-sharing octahedra tilt angles range from 16–56°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pu2O3 by Materials Project

Pu2O3 crystallizes in the cubic Pn-3m space group. The structure is three-dimensional. Pu3+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Pu–O bond lengths are 2.33 Å. O2- is bonded to four equivalent Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pu2O3 by Materials Project

Pu2O3 is Spinel-derived structured and crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are four inequivalent Pu3+ sites. In the first Pu3+ site, Pu3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing PuO6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are a spread of Pu–O bond distances ranging from 2.29–2.41 Å. In the second Pu3+ site, Pu3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing PuO6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are a spread of Pu–O bond distances ranging from 2.30–2.40 Å. In the third Pu3+ site, Pu3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing PuO6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are four shorter (2.34 Å) and two longer (2.35 Å) Pu–O bond lengths. In the fourth Pu3+ site, Pu3+ is bonded to six equivalent O2- atoms to form a mixture of distorted edge and corner-sharing PuO6 octahedra. The corner-sharing octahedral tilt angles are 57°. All Pu–O bond lengths are 2.32 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra. In the second O2- site, O2- is bonded to four Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra. In the third O2- site, O2- is bonded to four Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra. In the fourth O2- site, O2- is bonded to four Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PuO by Materials Project

PuO is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Pu is bonded to six equivalent O atoms to form a mixture of corner and edge-sharing PuO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Pu–O bond lengths are 2.49 Å. O is bonded to six equivalent Pu atoms to form a mixture of corner and edge-sharing OPu6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PuO2 by Materials Project

PuO2 is Hydrophilite-like structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Pu4+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing PuO6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Pu–O bond lengths are 2.23 Å. O2- is bonded in a trigonal planar geometry to three equivalent Pu4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pu3O2 by Materials Project

Pu3O2 is Corundum structured and crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Pu is bonded in a distorted rectangular see-saw-like geometry to four equivalent O atoms. There are two shorter (2.46 Å) and two longer (2.53 Å) Pu–O bond lengths. O is bonded to six equivalent Pu atoms to form a mixture of edge, corner, and face-sharing OPu6 octahedra. The corner-sharing octahedra tilt angles range from 49–50°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pu2O3 by Materials Project

Pu2O3 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Pu3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are four shorter (2.31 Å) and two longer (2.41 Å) Pu–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra. In the third O2- site, O2- is bonded to four equivalent Pu3+ atoms to form a mixture of edge and corner-sharing OPu4 tetrahedra.

36 MATERIALS SCIENCE↗