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At least 1,063 records · Page 59
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DOE OSTI2020

Materials Data on NbFe4Si by Materials Project

NbFe4Si crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Nb is bonded in a 1-coordinate geometry to three equivalent Nb, twelve Fe, and one Si atom. All Nb–Nb bond lengths are 3.03 Å. There are a spread of Nb–Fe bond distances ranging from 2.73–2.89 Å. The Nb–Si bond length is 2.72 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six equivalent Nb and six equivalent Fe atoms to form FeNb6Fe6 cuboctahedra that share corners with twelve equivalent FeNb3Fe6Si3 cuboctahedra, edges with six equivalent FeNb6Fe6 cuboctahedra, and faces with twenty FeFe6Si6 cuboctahedra. All Fe–Fe bond lengths are 2.40 Å. In the second Fe site, Fe is bonded to six equivalent Fe and six equivalent Si atoms to form FeFe6Si6 cuboctahedra that share corners with twelve equivalent FeNb3Fe6Si3 cuboctahedra, edges with six equivalent FeFe6Si6 cuboctahedra, and faces with twenty FeNb6Fe6 cuboctahedra. All Fe–Fe bond lengths are 2.31 Å. All Fe–Si bond lengths are 2.80 Å. In the third Fe site, Fe is bonded to three equivalent Nb, six Fe, and three equivalent Si atoms to form FeNb3Fe6Si3 cuboctahedra that share corners with eighteen FeNb6Fe6 cuboctahedra, edges with six equivalent FeNb3Fe6Si3 cuboctahedra, and faces with eighteen FeNb6Fe6 cuboctahedra. There are two shorter (2.35 Å) and two longer (2.44 Å) Fe–Fe bond lengths. There are one shorter (2.64 Å) and two longer (2.78 Å) Fe–Si bond lengths. Si is bonded in a 1-coordinate geometry to one Nb and twelve Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg6NbC by Materials Project

Mg6NbC crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a single-bond geometry to two equivalent Mg, two equivalent Nb, and one C atom. Both Mg–Mg bond lengths are 3.19 Å. There are one shorter (3.21 Å) and one longer (3.36 Å) Mg–Nb bond lengths. The Mg–C bond length is 2.35 Å. In the second Mg site, Mg is bonded in a 2-coordinate geometry to one Mg, two equivalent Nb, and two equivalent C atoms. The Mg–Mg bond length is 2.91 Å. Both Mg–Nb bond lengths are 2.94 Å. Both Mg–C bond lengths are 2.67 Å. In the third Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Mg and two equivalent Nb atoms. Both Mg–Mg bond lengths are 2.80 Å. Both Mg–Nb bond lengths are 2.88 Å. In the fourth Mg site, Mg is bonded in a 8-coordinate geometry to eight Mg atoms. Nb is bonded to ten Mg and two equivalent C atoms to form a mixture of distorted face and corner-sharing NbMg10C2 cuboctahedra. Both Nb–C bond lengths are 2.94 Å. C is bonded in a 8-coordinate geometry to six Mg and two equivalent Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3S4 by Materials Project

Nb3S4 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Nb3S4 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Nb+2.67+ sites. In the first Nb+2.67+ site, Nb+2.67+ is bonded to six S2- atoms to form a mixture of distorted edge, face, and corner-sharing NbS6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 44°. There are three shorter (2.48 Å) and three longer (2.53 Å) Nb–S bond lengths. In the second Nb+2.67+ site, Nb+2.67+ is bonded to six equivalent S2- atoms to form a mixture of edge, face, and corner-sharing NbS6 octahedra. All Nb–S bond lengths are 2.55 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to six Nb+2.67+ atoms to form a mixture of distorted edge and corner-sharing SNb6 pentagonal pyramids. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Nb+2.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsMg6Nb by Materials Project

CsMg6Nb crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Cs is bonded to twelve Mg atoms to form CsMg12 cuboctahedra that share corners with four equivalent CsMg12 cuboctahedra, edges with eight equivalent MgCs2Mg8Nb2 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, and faces with four equivalent MgCs2Mg8Nb2 cuboctahedra. There are a spread of Cs–Mg bond distances ranging from 3.59–3.63 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Cs, eight Mg, and two equivalent Nb atoms to form MgCs2Mg8Nb2 cuboctahedra that share corners with twelve equivalent MgCs2Mg8Nb2 cuboctahedra, edges with four equivalent CsMg12 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, and faces with six equivalent MgCs2Mg8Nb2 cuboctahedra. There are four shorter (3.30 Å) and four longer (3.32 Å) Mg–Mg bond lengths. There are one shorter (3.57 Å) and one longer (3.62 Å) Mg–Nb bond lengths. In the second Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Nb atoms. There are one shorter (2.97 Å) and one longer (2.98 Å) Mg–Mg bond lengths. Both Mg–Nb bond lengths are 2.95 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Nb atoms. Both Mg–Nb bond lengths are 2.96 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Nb atoms. Both Mg–Nb bond lengths are 2.95 Å. Nb is bonded in a 12-coordinate geometry to twelve Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3(Ni10B3)2 by Materials Project

Nb3(Ni10B3)2 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a distorted tetrahedral geometry to four equivalent Ni atoms. All Nb–Ni bond lengths are 2.47 Å. In the second Nb site, Nb is bonded in a distorted cuboctahedral geometry to twelve equivalent Ni atoms. All Nb–Ni bond lengths are 2.57 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded to one Nb and three equivalent B atoms to form a mixture of distorted edge and corner-sharing NiNbB3 tetrahedra. All Ni–B bond lengths are 2.13 Å. In the second Ni site, Ni is bonded in a 2-coordinate geometry to one Nb and two equivalent B atoms. Both Ni–B bond lengths are 2.08 Å. B is bonded in a 8-coordinate geometry to eight Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KMg6Nb by Materials Project

KMg6Nb crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. K is bonded to twelve Mg atoms to form KMg12 cuboctahedra that share corners with four equivalent KMg12 cuboctahedra, corners with eight equivalent NbMg12 cuboctahedra, edges with eight equivalent MgK2Mg8Nb2 cuboctahedra, faces with two equivalent KMg12 cuboctahedra, faces with four equivalent MgK2Mg8Nb2 cuboctahedra, and faces with four equivalent NbMg12 cuboctahedra. There are a spread of K–Mg bond distances ranging from 3.27–3.50 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent K, eight Mg, and two equivalent Nb atoms to form distorted MgK2Mg8Nb2 cuboctahedra that share corners with twelve equivalent MgK2Mg8Nb2 cuboctahedra, edges with four equivalent KMg12 cuboctahedra, edges with four equivalent NbMg12 cuboctahedra, faces with two equivalent KMg12 cuboctahedra, faces with two equivalent NbMg12 cuboctahedra, and faces with six equivalent MgK2Mg8Nb2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.30 Å. There are one shorter (3.25 Å) and one longer (3.31 Å) Mg–Nb bond lengths. In the second Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent K, six Mg, and two equivalent Nb atoms. There are one shorter (2.87 Å) and one longer (2.90 Å) Mg–Mg bond lengths. Both Mg–Nb bond lengths are 3.06 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent K, six Mg, and two equivalent Nb atoms. Both Mg–Nb bond lengths are 3.07 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent K, six Mg, and two equivalent Nb atoms. Both Mg–Nb bond lengths are 3.09 Å. Nb is bonded to twelve Mg atoms to form NbMg12 cuboctahedra that share corners with four equivalent NbMg12 cuboctahedra, corners with eight equivalent KMg12 cuboctahedra, edges with eight equivalent MgK2Mg8Nb2 cuboctahedra, faces with two equivalent NbMg12 cuboctahedra, faces with four equivalent KMg12 cuboctahedra, and faces with four equivalent MgK2Mg8Nb2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbRh3 by Materials Project

Rh3Nb is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded to twelve Rh atoms to form NbRh12 cuboctahedra that share corners with twelve NbRh12 cuboctahedra, edges with eighteen equivalent RhNb4Rh8 cuboctahedra, faces with six equivalent NbRh12 cuboctahedra, and faces with six equivalent RhNb4Rh8 cuboctahedra. All Nb–Rh bond lengths are 2.77 Å. In the second Nb site, Nb is bonded to twelve Rh atoms to form NbRh12 cuboctahedra that share corners with six equivalent RhNb4Rh8 cuboctahedra, corners with nine NbRh12 cuboctahedra, edges with twelve equivalent RhNb4Rh8 cuboctahedra, faces with seven NbRh12 cuboctahedra, and faces with nine equivalent RhNb4Rh8 cuboctahedra. There are a spread of Nb–Rh bond distances ranging from 2.72–2.82 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to four Nb and eight Rh atoms to form distorted RhNb4Rh8 cuboctahedra that share corners with two equivalent NbRh12 cuboctahedra, corners with ten equivalent RhNb4Rh8 cuboctahedra, edges with seven NbRh12 cuboctahedra, edges with eight equivalent RhNb4Rh8 cuboctahedra, faces with four NbRh12 cuboctahedra, and faces with ten equivalent RhNb4Rh8 cuboctahedra. There are a spread of Rh–Rh bond distances ranging from 2.74–2.78 Å. In the second Rh site, Rh is bonded in a distorted see-saw-like geometry to four Nb and four equivalent Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4VSe8 by Materials Project

Nb4VSe8 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to six equivalent Se2- atoms to form distorted NbSe6 pentagonal pyramids that share edges with six equivalent NbSe6 pentagonal pyramids and faces with two equivalent VSe6 octahedra. All Nb–Se bond lengths are 2.62 Å. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with four equivalent VSe6 octahedra and edges with six NbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 48°. There are two shorter (2.58 Å) and four longer (2.65 Å) Nb–Se bond lengths. V2+ is bonded to six equivalent Se2- atoms to form VSe6 octahedra that share corners with twelve equivalent NbSe6 pentagonal pyramids and faces with two equivalent NbSe6 pentagonal pyramids. All V–Se bond lengths are 2.55 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Nb+3.50+ atoms. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.50+ and one V2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4NiSe8 by Materials Project

Nb4NiSe8 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to six equivalent Se2- atoms to form distorted NbSe6 pentagonal pyramids that share edges with six equivalent NbSe6 pentagonal pyramids and faces with two equivalent NiSe6 octahedra. All Nb–Se bond lengths are 2.63 Å. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with four equivalent NiSe6 octahedra and edges with six NbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 49°. There are two shorter (2.60 Å) and four longer (2.65 Å) Nb–Se bond lengths. Ni2+ is bonded to six equivalent Se2- atoms to form NiSe6 octahedra that share corners with twelve equivalent NbSe6 pentagonal pyramids and faces with two equivalent NbSe6 pentagonal pyramids. All Ni–Se bond lengths are 2.52 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Nb+3.50+ atoms. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.50+ and one Ni2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbCr4Si by Materials Project

NbCr4Si crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Nb is bonded in a 1-coordinate geometry to three equivalent Nb, twelve Cr, and one Si atom. All Nb–Nb bond lengths are 3.00 Å. There are six shorter (2.85 Å) and six longer (2.86 Å) Nb–Cr bond lengths. The Nb–Si bond length is 2.79 Å. There are three inequivalent Cr sites. In the first Cr site, Cr is bonded to six equivalent Nb and six equivalent Cr atoms to form CrNb6Cr6 cuboctahedra that share corners with twelve equivalent CrNb3Cr6Si3 cuboctahedra, edges with six equivalent CrNb6Cr6 cuboctahedra, and faces with twenty CrCr6Si6 cuboctahedra. All Cr–Cr bond lengths are 2.47 Å. In the second Cr site, Cr is bonded to six equivalent Cr and six equivalent Si atoms to form CrCr6Si6 cuboctahedra that share corners with twelve equivalent CrNb3Cr6Si3 cuboctahedra, edges with six equivalent CrCr6Si6 cuboctahedra, and faces with twenty CrNb6Cr6 cuboctahedra. All Cr–Cr bond lengths are 2.33 Å. All Cr–Si bond lengths are 2.86 Å. In the third Cr site, Cr is bonded to three equivalent Nb, six Cr, and three equivalent Si atoms to form CrNb3Cr6Si3 cuboctahedra that share corners with eighteen CrNb6Cr6 cuboctahedra, edges with six equivalent CrNb3Cr6Si3 cuboctahedra, and faces with eighteen CrNb6Cr6 cuboctahedra. There are two shorter (2.37 Å) and two longer (2.51 Å) Cr–Cr bond lengths. There are one shorter (2.71 Å) and two longer (2.76 Å) Cr–Si bond lengths. Si is bonded in a 10-coordinate geometry to one Nb and twelve Cr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Adsorption and Surface Diffusion of Metals on α-Al2O3 for Advanced Manufacturing Applications

Abstract The adsorption and diffusion of Mo and Nb adatoms on the $$\alpha$$ α -Al 2 O 3 (0001) surface were explored using density functional theory-based methods. Adsorption energies of Mo and Nb adatoms at minima sites on the surface were determined. Mo and Nb adatoms prefer to adsorb to the same locations on the surface, and larger adsorption energies calculated for Nb compared to Mo indicate that Nb adatom-surface interactions are stronger than Mo. Using minima adsorption sites as initial and final locations for surface diffusion, energy barriers for diffusion were calculated using the nudged elastic band method. Overall, Mo and Nb follow roughly the same diffusion paths. The diffusion pre-factors for Mo and Nb are similar; however, Mo diffusion has a lower energy barrier and thus a larger diffusion coefficient compared with Nb. These results provide insight into the role of surface diffusion of Mo and Nb adatoms during advanced manufacturing processes.

Biaggne, Austin (ORCID:0000000328074960)↗
DOE OSTI2022

Stability, metallicity, and magnetism in niobium silicide nanofilms

Modern superconducting qubits based on two-dimensional (2D) transmons typically involve the growth of Nb thin films on high-resistivity Si substrates. Since imperfections at the Nb-Si heterointerface have been implicated as a source of two-level systems that limit quantum coherence times, detailed characterization and understanding of niobium silicide interfacial layers are critical to improving superconducting qubit technology. While bulk binary intermetallic niobium silicide phases are well understood, the thermodynamic phase stability and properties of ultrathin niobium silicides, such as those found at the Nb-Si heterointerface in 2D transmons, have not yet been explored. Here, we report finite-sized effects for ultrathin niobium silicide films using density functional theory calculations and predict nanoscale stabilization of Nb 6 Si 5 over the bulk α-Nb 5 Si 3 phase. This result is consistent with our experimental observations of a niobium silicide interfacial layer between a sputtered Nb thin film and the underlying Si substrate. Furthermore, our calculations show that Nb 6 Si 5 nanofilms are nonmagnetic, making them superior to nanofilms of α-Nb 5 Si 3 that exhibit antiferromagnetic correlations detrimental to long coherence times in superconducting qubits. Furthermore, by providing atomic-scale insight into niobium silicide nanofilms, this paper can help guide ongoing efforts to optimize Nb-Si heterointerfaces for long coherence times in superconducting qubits.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(NbS2)3 by Materials Project

MnNb3S6 is Ilmenite-like structured and crystallizes in the hexagonal P6_322 space group. The structure is three-dimensional. there are two inequivalent Nb+3.33+ sites. In the first Nb+3.33+ site, Nb+3.33+ is bonded to six equivalent S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with three equivalent MnS6 octahedra, edges with six NbS6 pentagonal pyramids, and a faceface with one MnS6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are three shorter (2.49 Å) and three longer (2.52 Å) Nb–S bond lengths. In the second Nb+3.33+ site, Nb+3.33+ is bonded to six equivalent S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with six equivalent MnS6 octahedra and edges with six equivalent NbS6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 46°. All Nb–S bond lengths are 2.49 Å. Mn2+ is bonded to six equivalent S2- atoms to form MnS6 octahedra that share corners with twelve NbS6 pentagonal pyramids and faces with two equivalent NbS6 pentagonal pyramids. All Mn–S bond lengths are 2.49 Å. S2- is bonded in a rectangular see-saw-like geometry to three Nb+3.33+ and one Mn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb2Co3Si by Materials Project

Nb2Co3Si is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Nb is bonded in a 12-coordinate geometry to four equivalent Nb, nine equivalent Co, and three equivalent Si atoms. There are one shorter (2.87 Å) and three longer (2.95 Å) Nb–Nb bond lengths. There are three shorter (2.72 Å) and six longer (2.83 Å) Nb–Co bond lengths. All Nb–Si bond lengths are 2.85 Å. Co is bonded to six equivalent Nb, four equivalent Co, and two equivalent Si atoms to form CoNb6Co4Si2 cuboctahedra that share corners with four equivalent SiNb6Co6 cuboctahedra, corners with fourteen equivalent CoNb6Co4Si2 cuboctahedra, edges with six equivalent CoNb6Co4Si2 cuboctahedra, faces with six equivalent SiNb6Co6 cuboctahedra, and faces with twelve equivalent CoNb6Co4Si2 cuboctahedra. There are two shorter (2.39 Å) and two longer (2.48 Å) Co–Co bond lengths. Both Co–Si bond lengths are 2.37 Å. Si is bonded to six equivalent Nb and six equivalent Co atoms to form SiNb6Co6 cuboctahedra that share corners with twelve equivalent CoNb6Co4Si2 cuboctahedra, edges with six equivalent SiNb6Co6 cuboctahedra, faces with two equivalent SiNb6Co6 cuboctahedra, and faces with eighteen equivalent CoNb6Co4Si2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb5(NiP)4 by Materials Project

Nb5(NiP)4 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a 5-coordinate geometry to five equivalent P atoms. There are a spread of Nb–P bond distances ranging from 2.59–2.72 Å. In the second Nb site, Nb is bonded in a square co-planar geometry to four equivalent P atoms. All Nb–P bond lengths are 2.65 Å. Ni is bonded in a 3-coordinate geometry to three equivalent P atoms. There are two shorter (2.22 Å) and one longer (2.27 Å) Ni–P bond lengths. P is bonded in a 9-coordinate geometry to six Nb and three equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3Ga2 by Materials Project

Nb3Ga2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a square co-planar geometry to four equivalent Ga atoms. All Nb–Ga bond lengths are 2.74 Å. In the second Nb site, Nb is bonded in a 6-coordinate geometry to six equivalent Ga atoms. There are two shorter (2.63 Å) and four longer (2.76 Å) Nb–Ga bond lengths. Ga is bonded in a 9-coordinate geometry to eight Nb and one Ga atom. The Ga–Ga bond length is 2.48 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb5(CuSi)4 by Materials Project

Nb5Cu4Si4 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Nb+2.40+ sites. In the first Nb+2.40+ site, Nb+2.40+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Nb–Si bond lengths are 2.66 Å. In the second Nb+2.40+ site, Nb+2.40+ is bonded to five equivalent Si4- atoms to form a mixture of distorted edge and corner-sharing NbSi5 trigonal bipyramids. There are a spread of Nb–Si bond distances ranging from 2.61–2.79 Å. Cu1+ is bonded in a distorted trigonal planar geometry to three equivalent Si4- atoms. There are two shorter (2.34 Å) and one longer (2.38 Å) Cu–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to six Nb+2.40+ and three equivalent Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li7NbN4 by Materials Project

Li7NbN4 is alpha bismuth trifluoride-derived structured and crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four N3- atoms to form LiN4 tetrahedra that share corners with four equivalent NbN4 tetrahedra, corners with twelve LiN4 tetrahedra, and edges with six LiN4 tetrahedra. There are one shorter (2.15 Å) and three longer (2.19 Å) Li–N bond lengths. In the second Li1+ site, Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent NbN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one NbN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.10–2.24 Å. In the third Li1+ site, Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent NbN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one NbN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.11–2.26 Å. Nb5+ is bonded to four N3- atoms to form NbN4 tetrahedra that share corners with sixteen LiN4 tetrahedra and edges with six LiN4 tetrahedra. There is one shorter (1.97 Å) and three longer (1.99 Å) Nb–N bond length. There are eleven inequivalent N3- sites. In the first N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. All N–Li bond lengths are 2.11 Å. In the second N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are one shorter (2.15 Å) and three longer (2.24 Å) N–Li bond lengths. The N–Nb bond length is 1.97 Å. In the third N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.15–2.26 Å. The N–Nb bond length is 1.99 Å. In the fourth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. In the fifth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.21 Å. In the sixth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Nb bond length is 1.99 Å. In the seventh N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Nb bond length is 1.99 Å. In the eighth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. In the ninth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.15–2.26 Å. The N–Nb bond length is 1.99 Å. In the tenth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Nb bond length is 1.99 Å. In the eleventh N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.21 Å. The N–Nb bond length is 1.99 Å.

36 MATERIALS SCIENCE↗