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4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

HfZr_BCC_SolidSolution_128atoms_VASP6

We performed density functional theory (DFT) calculations for body-centered-cubic (BCC) structures with 128 lattices sites of solid solution binary alloys hafnium-zirconium (Hf-Zr). The electronic structures of alloys have been calculated using Vienna Ab initio Simulation Package (VASP). Within this package the DFT approach is used to reduce many-body Schrodinger equation to set of single particle Kohn-Sham (KS) equations. The generalized electronic exchange-correlation functional is described by generalized gradient approximation with the Perdew-Burke-Ernzerhof parametrization. The electron-ion interactions is described by pseudopotentials developed within the plane-wave basis projector augmented-wave (PAW) approach. These pseudopotentials are available at the VASP portal (http://cms.mpi.univie.ac.at/vasp/). Our calculations have been run with the pseudopotentials treating s and p semi-core states as valence in case for the elements Hf and Zr. The electronic densities and potentials are expanded over plane-waves with energy cutoff of 350 eV. 2x2x2 k-mesh and normal precision were used. The alloys were modeled by supercell containing 128 randomly distributed atoms. At initial step the atoms occupy perfect bcc lattice cites. This initial structure was optimized until energy changes less than 1e-6 eV, while forces acting on atoms don't exceed 1e-2 eV/angstrom. The electron-ion interaction is described by PAW pseudopotentials. The calculations have been collected by sampling chemical compositions across the entire compositional range. The chemical compositions have been sampled by progressively changing the number of atoms per constituent by 4. For each chemical composition of binaries and ternaries, the first-principle calculations have been run for 100 randomized arrangements of the constituents on the BCC lattice sites. We collected data for a total of 3,100 randomized atomic structures over 31 chemical compositions.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfZr by Materials Project

HfZr is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Hf is bonded to six equivalent Hf and six equivalent Zr atoms to form HfHf6Zr6 cuboctahedra that share corners with eighteen equivalent HfHf6Zr6 cuboctahedra, edges with six equivalent HfHf6Zr6 cuboctahedra, edges with twelve equivalent ZrHf6Zr6 cuboctahedra, faces with eight equivalent HfHf6Zr6 cuboctahedra, and faces with twelve equivalent ZrHf6Zr6 cuboctahedra. All Hf–Hf bond lengths are 3.22 Å. All Hf–Zr bond lengths are 3.17 Å. Zr is bonded to six equivalent Hf and six equivalent Zr atoms to form ZrHf6Zr6 cuboctahedra that share corners with eighteen equivalent ZrHf6Zr6 cuboctahedra, edges with six equivalent ZrHf6Zr6 cuboctahedra, edges with twelve equivalent HfHf6Zr6 cuboctahedra, faces with eight equivalent ZrHf6Zr6 cuboctahedra, and faces with twelve equivalent HfHf6Zr6 cuboctahedra. All Zr–Zr bond lengths are 3.22 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfZr(SbRh)2 by Materials Project

HfZr(RhSb)2 is half-Heusler-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to four Rh and four Sb atoms. There are one shorter (2.74 Å) and three longer (2.82 Å) Hf–Rh bond lengths. There are one shorter (2.80 Å) and three longer (2.81 Å) Hf–Sb bond lengths. Zr is bonded in a body-centered cubic geometry to four Rh and four Sb atoms. There are one shorter (2.82 Å) and three longer (2.84 Å) Zr–Rh bond lengths. There are three shorter (2.83 Å) and one longer (2.85 Å) Zr–Sb bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to one Hf and three equivalent Zr atoms to form distorted RhHfZr3 tetrahedra that share corners with four equivalent SbHfZr3 tetrahedra, corners with twelve RhHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. In the second Rh site, Rh is bonded to three equivalent Hf and one Zr atom to form distorted RhHf3Zr tetrahedra that share corners with four equivalent SbHf3Zr tetrahedra, corners with twelve RhHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. There are two inequivalent Sb sites. In the first Sb site, Sb is bonded to three equivalent Hf and one Zr atom to form distorted SbHf3Zr tetrahedra that share corners with four equivalent RhHf3Zr tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six RhHfZr3 tetrahedra. In the second Sb site, Sb is bonded to one Hf and three equivalent Zr atoms to form distorted SbHfZr3 tetrahedra that share corners with four equivalent RhHfZr3 tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six RhHfZr3 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfZr(CoSb)2 by Materials Project

HfZr(CoSb)2 is half-Heusler-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to four Co and four Sb atoms. There are one shorter (2.76 Å) and three longer (2.80 Å) Hf–Co bond lengths. There are one shorter (2.78 Å) and three longer (2.79 Å) Hf–Sb bond lengths. Zr is bonded in a body-centered cubic geometry to four Co and four Sb atoms. There are three shorter (2.81 Å) and one longer (2.82 Å) Zr–Co bond lengths. All Zr–Sb bond lengths are 2.82 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded to one Hf and three equivalent Zr atoms to form distorted CoHfZr3 tetrahedra that share corners with four equivalent SbHfZr3 tetrahedra, corners with twelve CoHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. In the second Co site, Co is bonded to three equivalent Hf and one Zr atom to form distorted CoHf3Zr tetrahedra that share corners with four equivalent SbHf3Zr tetrahedra, corners with twelve CoHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. There are two inequivalent Sb sites. In the first Sb site, Sb is bonded to three equivalent Hf and one Zr atom to form distorted SbHf3Zr tetrahedra that share corners with four equivalent CoHf3Zr tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six CoHfZr3 tetrahedra. In the second Sb site, Sb is bonded to one Hf and three equivalent Zr atoms to form distorted SbHfZr3 tetrahedra that share corners with four equivalent CoHfZr3 tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six CoHfZr3 tetrahedra.

36 MATERIALS SCIENCE↗