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DOE OSTI2020

Materials Data on Li3Nb4O12 by Materials Project

Li3Nb4O12 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are three inequivalent Li sites. In the first Li site, Li is bonded in a 6-coordinate geometry to six O atoms. There are three shorter (2.06 Å) and three longer (2.42 Å) Li–O bond lengths. In the second Li site, Li is bonded in a 6-coordinate geometry to six O atoms. There are three shorter (2.08 Å) and three longer (2.41 Å) Li–O bond lengths. In the third Li site, Li is bonded in a distorted trigonal planar geometry to six O atoms. There are three shorter (2.01 Å) and three longer (2.56 Å) Li–O bond lengths. There are four inequivalent Nb sites. In the first Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 24–40°. There are three shorter (1.91 Å) and three longer (2.12 Å) Nb–O bond lengths. In the second Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 37–38°. There are three shorter (1.94 Å) and three longer (2.10 Å) Nb–O bond lengths. In the third Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 37–40°. There are three shorter (1.93 Å) and three longer (2.12 Å) Nb–O bond lengths. In the fourth Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 24–38°. There are three shorter (1.92 Å) and three longer (2.10 Å) Nb–O bond lengths. There are four inequivalent O sites. In the first O site, O is bonded in a distorted see-saw-like geometry to two Li and two Nb atoms. In the second O site, O is bonded in a distorted trigonal planar geometry to one Li and two Nb atoms. In the third O site, O is bonded in a distorted trigonal planar geometry to one Li and two Nb atoms. In the fourth O site, O is bonded in a 4-coordinate geometry to two Li and two Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li4Ti5Nb3O16 by Materials Project

Li4Ti5Nb3O16 is Spinel-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with five NbO6 octahedra and corners with seven TiO6 octahedra. The corner-sharing octahedra tilt angles range from 52–61°. There are a spread of Li–O bond distances ranging from 1.94–1.99 Å. In the second Li1+ site, Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.80–2.05 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one NbO6 octahedra, corners with five TiO6 octahedra, an edgeedge with one TiO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 57–62°. There are a spread of Li–O bond distances ranging from 1.80–2.04 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with four NbO6 octahedra and corners with eight TiO6 octahedra. The corner-sharing octahedra tilt angles range from 41–63°. There are a spread of Li–O bond distances ranging from 1.88–2.02 Å. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four LiO4 tetrahedra, edges with two equivalent NbO6 octahedra, and edges with three TiO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Ti–O bond distances ranging from 1.99–2.12 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four equivalent NbO6 octahedra, corners with six LiO4 tetrahedra, an edgeedge with one NbO6 octahedra, and edges with two equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 52–54°. There are a spread of Ti–O bond distances ranging from 1.92–2.20 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with three LiO4 tetrahedra, an edgeedge with one TiO6 octahedra, edges with four equivalent NbO6 octahedra, and an edgeedge with one LiO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ti–O bond distances ranging from 1.99–2.16 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent TiO6 octahedra, corners with three equivalent LiO4 tetrahedra, an edgeedge with one TiO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 51–52°. There are a spread of Ti–O bond distances ranging from 2.01–2.11 Å. There are two inequivalent Nb+2.67+ sites. In the first Nb+2.67+ site, Nb+2.67+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four LiO4 tetrahedra, and edges with five TiO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Nb–O bond distances ranging from 2.06–2.09 Å. In the second Nb+2.67+ site, Nb+2.67+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with three LiO4 tetrahedra, edges with two equivalent NbO6 octahedra, edges with three TiO6 octahedra, and an edgeedge with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–54°. There are a spread of Nb–O bond distances ranging from 2.09–2.23 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+, two Ti4+, and one Nb+2.67+ atom. In the second O2- site, O2- is bonded to one Li1+ and three Ti4+ atoms to form a mixture of distorted edge and corner-sharing OLiTi3 tetrahedra. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+, two equivalent Ti4+, and one Nb+2.67+ atom. In the fourth O2- site, O2- is bonded to one Li1+, two equivalent Ti4+, and one Nb+2.67+ atom to form distorted corner-sharing OLiTi2Nb tetrahedra. In the fifth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Li1+, one Ti4+, and two equivalent Nb+2.67+ atoms. In the sixth O2- site, O2- is bonded to one Li1+, two Ti4+, and one Nb+2.67+ atom to form a mixture of distorted edge and corner-sharing OLiTi2Nb tetrahedra. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+ and three Ti4+ atoms. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, one Ti4+, and two equivalent Nb+2.67+ atoms. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, two Ti4+, and one Nb+2.67+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, one Ti4+, and two equivalent Nb+2.67+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+, two Ti4+, and one Nb+2.67+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, one Ti4+, and two equivalent Nb+2.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4ReO4 by Materials Project

Nb4ReO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Nb sites. In the first Nb site, Nb is bonded in a distorted see-saw-like geometry to four O atoms. There are a spread of Nb–O bond distances ranging from 2.13–2.22 Å. In the second Nb site, Nb is bonded in a 4-coordinate geometry to four O atoms. There are a spread of Nb–O bond distances ranging from 2.02–2.26 Å. In the third Nb site, Nb is bonded in a 3-coordinate geometry to three O atoms. There are a spread of Nb–O bond distances ranging from 2.14–2.20 Å. In the fourth Nb site, Nb is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Nb–O bond distances ranging from 2.10–2.43 Å. Re is bonded in a 3-coordinate geometry to three O atoms. There are a spread of Re–O bond distances ranging from 2.02–2.16 Å. There are four inequivalent O sites. In the first O site, O is bonded to three Nb and one Re atom to form distorted ONb3Re trigonal pyramids that share corners with seven ONb4Re trigonal bipyramids and an edgeedge with one ONb3Re trigonal pyramid. In the second O site, O is bonded to five Nb atoms to form ONb5 trigonal bipyramids that share corners with six ONb4Re trigonal bipyramids, a cornercorner with one ONb3Re trigonal pyramid, and edges with five ONb4Re trigonal bipyramids. In the third O site, O is bonded to four Nb and one Re atom to form distorted ONb4Re trigonal bipyramids that share corners with four ONb4Re trigonal bipyramids, corners with four equivalent ONb3Re trigonal pyramids, and edges with three ONb4Re trigonal bipyramids. In the fourth O site, O is bonded to four Nb and one Re atom to form ONb4Re trigonal bipyramids that share corners with four ONb5 trigonal bipyramids, corners with two equivalent ONb3Re trigonal pyramids, and edges with five ONb4Re trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3Se5Br7 by Materials Project

Nb3Se5Br7 crystallizes in the monoclinic P2_1/m space group. The structure is one-dimensional and consists of one Nb3Se5Br7 ribbon oriented in the (0, 1, 0) direction. there are two inequivalent Nb+3.67+ sites. In the first Nb+3.67+ site, Nb+3.67+ is bonded in a 8-coordinate geometry to four Se2- and four Br+0.14- atoms. All Nb–Se bond lengths are 2.65 Å. There are a spread of Nb–Br bond distances ranging from 2.74–2.82 Å. In the second Nb+3.67+ site, Nb+3.67+ is bonded in a distorted octahedral geometry to one Se2- and five Br+0.14- atoms. The Nb–Se bond length is 2.30 Å. There are a spread of Nb–Br bond distances ranging from 2.49–2.96 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a single-bond geometry to one Nb+3.67+ atom. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Nb+3.67+ atoms. In the third Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Nb+3.67+ atoms. There are five inequivalent Br+0.14- sites. In the first Br+0.14- site, Br+0.14- is bonded in a distorted water-like geometry to two Nb+3.67+ atoms. In the second Br+0.14- site, Br+0.14- is bonded in a single-bond geometry to one Nb+3.67+ atom. In the third Br+0.14- site, Br+0.14- is bonded in a 3-coordinate geometry to three Nb+3.67+ atoms. In the fourth Br+0.14- site, Br+0.14- is bonded in an L-shaped geometry to two equivalent Nb+3.67+ atoms. In the fifth Br+0.14- site, Br+0.14- is bonded in a distorted L-shaped geometry to two equivalent Nb+3.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta6Nb3Te2S3 by Materials Project

Ta6Nb3Te2S3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are six inequivalent Ta sites. In the first Ta site, Ta is bonded in a 3-coordinate geometry to four S atoms. There are a spread of Ta–S bond distances ranging from 2.48–3.06 Å. In the second Ta site, Ta is bonded in a 8-coordinate geometry to four Te atoms. There are two shorter (2.88 Å) and two longer (2.89 Å) Ta–Te bond lengths. In the third Ta site, Ta is bonded in a distorted body-centered cubic geometry to eight Ta atoms. There are a spread of Ta–Ta bond distances ranging from 2.85–2.92 Å. In the fourth Ta site, Ta is bonded in a distorted single-bond geometry to two equivalent Ta, one Te, and one S atom. The Ta–Te bond length is 3.11 Å. The Ta–S bond length is 2.71 Å. In the fifth Ta site, Ta is bonded in a distorted single-bond geometry to two equivalent Ta, one Te, and one S atom. The Ta–Te bond length is 3.10 Å. The Ta–S bond length is 2.65 Å. In the sixth Ta site, Ta is bonded in an L-shaped geometry to two equivalent Ta and two equivalent S atoms. Both Ta–S bond lengths are 2.53 Å. There are three inequivalent Nb sites. In the first Nb site, Nb is bonded in a 5-coordinate geometry to five S atoms. There are a spread of Nb–S bond distances ranging from 2.52–2.91 Å. In the second Nb site, Nb is bonded in a 3-coordinate geometry to two equivalent Te and three equivalent S atoms. Both Nb–Te bond lengths are 2.89 Å. There are one shorter (2.52 Å) and two longer (2.55 Å) Nb–S bond lengths. In the third Nb site, Nb is bonded in a 3-coordinate geometry to two equivalent Te and three S atoms. Both Nb–Te bond lengths are 2.94 Å. There are one shorter (2.49 Å) and two longer (2.50 Å) Nb–S bond lengths. There are two inequivalent Te sites. In the first Te site, Te is bonded in a 5-coordinate geometry to three Ta and two equivalent Nb atoms. In the second Te site, Te is bonded in a 5-coordinate geometry to three Ta and two equivalent Nb atoms. There are three inequivalent S sites. In the first S site, S is bonded in a 9-coordinate geometry to four Ta and five Nb atoms. In the second S site, S is bonded in a 6-coordinate geometry to three Ta and three equivalent Nb atoms. In the third S site, S is bonded in a rectangular see-saw-like geometry to one Ta and three Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaMg6Nb by Materials Project

NaMg6Nb is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Na is bonded to ten Mg and two equivalent Nb atoms to form NaMg10Nb2 cuboctahedra that share corners with four equivalent MgNa2Mg10 cuboctahedra, corners with six equivalent NaMg10Nb2 cuboctahedra, edges with four equivalent NbNa2Mg10 cuboctahedra, edges with ten MgNa2Mg10 cuboctahedra, faces with two equivalent NaMg10Nb2 cuboctahedra, faces with two equivalent NbNa2Mg10 cuboctahedra, and faces with twelve MgNa2Mg10 cuboctahedra. There are a spread of Na–Mg bond distances ranging from 3.06–3.27 Å. Both Na–Nb bond lengths are 3.23 Å. There are eight inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Na, eight Mg, and two equivalent Nb atoms. There are a spread of Mg–Mg bond distances ranging from 3.00–3.40 Å. Both Mg–Nb bond lengths are 3.04 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Na, eight Mg, and two equivalent Nb atoms. There are a spread of Mg–Mg bond distances ranging from 3.00–3.40 Å. Both Mg–Nb bond lengths are 3.04 Å. In the third Mg site, Mg is bonded to two equivalent Na and ten Mg atoms to form MgNa2Mg10 cuboctahedra that share corners with four equivalent NaMg10Nb2 cuboctahedra, corners with six equivalent MgNa2Mg10 cuboctahedra, edges with two equivalent NaMg10Nb2 cuboctahedra, edges with twelve MgNa2Mg8Nb2 cuboctahedra, faces with two equivalent NaMg10Nb2 cuboctahedra, faces with six equivalent NbNa2Mg10 cuboctahedra, and faces with eight MgNa2Mg10 cuboctahedra. There are four shorter (3.15 Å) and three longer (3.16 Å) Mg–Mg bond lengths. In the fourth Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent Nb atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent NbNa2Mg10 cuboctahedra, corners with fourteen MgNa2Mg8Nb2 cuboctahedra, edges with two equivalent NbNa2Mg10 cuboctahedra, edges with four equivalent NaMg10Nb2 cuboctahedra, edges with eight MgNa2Mg10 cuboctahedra, faces with two equivalent NaMg10Nb2 cuboctahedra, faces with two equivalent NbNa2Mg10 cuboctahedra, and faces with eight MgNa2Mg10 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.13–3.21 Å. There are one shorter (3.04 Å) and one longer (3.29 Å) Mg–Nb bond lengths. In the fifth Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent Nb atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent NbNa2Mg10 cuboctahedra, corners with fourteen MgNa2Mg8Nb2 cuboctahedra, edges with two equivalent NbNa2Mg10 cuboctahedra, edges with four equivalent NaMg10Nb2 cuboctahedra, edges with eight MgNa2Mg10 cuboctahedra, faces with two equivalent NaMg10Nb2 cuboctahedra, faces with two equivalent NbNa2Mg10 cuboctahedra, and faces with eight MgNa2Mg10 cuboctahedra. Both Mg–Na bond lengths are 3.15 Å. There are a spread of Mg–Mg bond distances ranging from 3.13–3.21 Å. There are one shorter (3.04 Å) and one longer (3.29 Å) Mg–Nb bond lengths. In the sixth Mg site, Mg is bonded to ten Mg and two equivalent Nb atoms to form MgMg10Nb2 cuboctahedra that share corners with four equivalent NbNa2Mg10 cuboctahedra, corners with fourteen MgNa2Mg8Nb2 cuboctahedra, edges with two equivalent NbNa2Mg10 cuboctahedra, edges with eight MgNa2Mg10 cuboctahedra, faces with two equivalent NbNa2Mg10 cuboctahedra, faces with six equivalent NaMg10Nb2 cuboctahedra, and faces with eight MgNa2Mg10 cuboctahedra. There are two shorter (3.17 Å) and one longer (3.20 Å) Mg–Mg bond lengths. Both Mg–Nb bond lengths are 3.20 Å. In the seventh Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Na, eight Mg, and two equivalent Nb atoms. Both Mg–Mg bond lengths are 3.18 Å. Both Mg–Nb bond lengths are 3.04 Å. In the eighth Mg site, Mg is bonded to two equivalent Na, eight Mg, and two equivalent Nb atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent NbNa2Mg10 cuboctahedra, corners with fourteen MgNa2Mg8Nb2 cuboctahedra, edges with two equivalent NbNa2Mg10 cuboctahedra, edges with four equivalent NaMg10Nb2 cuboctahedra, edges with eight MgNa2Mg10 cuboctahedra, faces with two equivalent NaMg10Nb2 cuboctahedra, faces with two equivalent NbNa2Mg10 cuboctahedra, and faces with eight MgNa2Mg10 cuboctahedra. Both Mg–Mg bond lengths are 3.18 Å. There are one shorter (3.04 Å) and one longer (3.29 Å) Mg–Nb bond lengths. Nb is bonded to two equivalent Na and ten Mg atoms to form NbNa2Mg10 cuboctahedra that share corners with six equivalent NbNa2Mg10 cuboctahedra, corners with twelve MgNa2Mg8Nb2 cuboctahedra, edges with four equivalent NaMg10Nb2 cuboctahedra, edges with six MgNa2Mg8Nb2 cuboctahedra, faces with two equivalent NaMg10Nb2 cuboctahedra, faces with two equivalent NbNa2Mg10 cuboctahedra, and faces with twelve MgNa2Mg10 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3MoSe8 by Materials Project

NbMoSe4(NbSe2)2 is Molybdenite-derived structured and crystallizes in the monoclinic Pm space group. The structure is two-dimensional and consists of one NbMoSe4 sheet oriented in the (0, 0, 1) direction and one NbSe2 sheet oriented in the (0, 0, 1) direction. In the NbMoSe4 sheet, Nb+4.67+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share edges with two equivalent NbSe6 pentagonal pyramids and edges with four equivalent MoSe6 pentagonal pyramids. There are four shorter (2.61 Å) and two longer (2.63 Å) Nb–Se bond lengths. Mo2+ is bonded to six Se2- atoms to form distorted MoSe6 pentagonal pyramids that share edges with two equivalent MoSe6 pentagonal pyramids and edges with four equivalent NbSe6 pentagonal pyramids. There are two shorter (2.57 Å) and four longer (2.58 Å) Mo–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to one Nb+4.67+ and two equivalent Mo2+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Nb+4.67+ and one Mo2+ atom. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Nb+4.67+ and one Mo2+ atom. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to one Nb+4.67+ and two equivalent Mo2+ atoms. In the NbSe2 sheet, there are two inequivalent Nb+4.67+ sites. In the first Nb+4.67+ site, Nb+4.67+ is bonded to six Se2- atoms to form distorted edge-sharing NbSe6 pentagonal pyramids. There are four shorter (2.62 Å) and two longer (2.63 Å) Nb–Se bond lengths. In the second Nb+4.67+ site, Nb+4.67+ is bonded to six Se2- atoms to form distorted edge-sharing NbSe6 pentagonal pyramids. There are four shorter (2.62 Å) and two longer (2.63 Å) Nb–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3WSe8 by Materials Project

Nb3WSe8 is Molybdenite-derived structured and crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of two Nb3WSe8 sheets oriented in the (1, 0, 0) direction. there are three inequivalent Nb+4.67+ sites. In the first Nb+4.67+ site, Nb+4.67+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share edges with two equivalent WSe6 pentagonal pyramids and edges with four NbSe6 pentagonal pyramids. There are two shorter (2.61 Å) and four longer (2.62 Å) Nb–Se bond lengths. In the second Nb+4.67+ site, Nb+4.67+ is bonded to six Se2- atoms to form distorted edge-sharing NbSe6 pentagonal pyramids. All Nb–Se bond lengths are 2.62 Å. In the third Nb+4.67+ site, Nb+4.67+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share edges with two equivalent WSe6 pentagonal pyramids and edges with four NbSe6 pentagonal pyramids. There are a spread of Nb–Se bond distances ranging from 2.60–2.64 Å. W2+ is bonded to six Se2- atoms to form distorted WSe6 pentagonal pyramids that share edges with two equivalent WSe6 pentagonal pyramids and edges with four NbSe6 pentagonal pyramids. There are one shorter (2.57 Å) and five longer (2.58 Å) W–Se bond lengths. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Nb+4.67+ and one W2+ atom. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to one Nb+4.67+ and two equivalent W2+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms. In the fifth Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms. In the sixth Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Nb+4.67+ and one W2+ atom. In the seventh Se2- site, Se2- is bonded in a 3-coordinate geometry to three Nb+4.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TiNb3(AlC)2 by Materials Project

TiNb3(AlC)2 is H-Phase-derived structured and crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. Ti is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Ti–Al bond lengths are 2.89 Å. All Ti–C bond lengths are 2.12 Å. There are three inequivalent Nb sites. In the first Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Nb–Al bond lengths are 2.88 Å. All Nb–C bond lengths are 2.21 Å. In the second Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Nb–Al bond lengths are 2.86 Å. All Nb–C bond lengths are 2.19 Å. In the third Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Nb–Al bond lengths are 2.88 Å. All Nb–C bond lengths are 2.19 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six Nb atoms to form distorted AlNb6 cuboctahedra that share corners with six CTi3Nb3 octahedra, edges with six equivalent AlNb6 cuboctahedra, and edges with six CTi3Nb3 octahedra. The corner-sharing octahedral tilt angles are 16°. In the second Al site, Al is bonded in a 12-coordinate geometry to three equivalent Ti and three equivalent Nb atoms. There are two inequivalent C sites. In the first C site, C is bonded to three equivalent Ti and three equivalent Nb atoms to form CTi3Nb3 octahedra that share corners with three equivalent AlNb6 cuboctahedra, edges with three equivalent AlNb6 cuboctahedra, and edges with six equivalent CTi3Nb3 octahedra. In the second C site, C is bonded to six Nb atoms to form CNb6 octahedra that share corners with three equivalent AlNb6 cuboctahedra, edges with three equivalent AlNb6 cuboctahedra, and edges with six equivalent CNb6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbReSi by Materials Project

NbReSi crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. there are three inequivalent Nb sites. In the first Nb site, Nb is bonded in a 11-coordinate geometry to six Re and five Si atoms. There are a spread of Nb–Re bond distances ranging from 2.80–2.89 Å. There are a spread of Nb–Si bond distances ranging from 2.67–2.99 Å. In the second Nb site, Nb is bonded in a 5-coordinate geometry to six Re and five Si atoms. There are a spread of Nb–Re bond distances ranging from 2.93–3.21 Å. There are a spread of Nb–Si bond distances ranging from 2.65–2.70 Å. In the third Nb site, Nb is bonded in a 9-coordinate geometry to six Re and five Si atoms. There are four shorter (2.88 Å) and two longer (3.13 Å) Nb–Re bond lengths. There are a spread of Nb–Si bond distances ranging from 2.68–2.71 Å. There are two inequivalent Re sites. In the first Re site, Re is bonded in a 12-coordinate geometry to six Nb, two equivalent Re, and four Si atoms. Both Re–Re bond lengths are 2.93 Å. There are two shorter (2.51 Å) and two longer (2.58 Å) Re–Si bond lengths. In the second Re site, Re is bonded in a 8-coordinate geometry to six Nb, three Re, and four Si atoms. There are one shorter (2.98 Å) and one longer (3.02 Å) Re–Re bond lengths. There are a spread of Re–Si bond distances ranging from 2.43–2.56 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to three Nb and six Re atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to six Nb and three Re atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba5Ca2Nb3O15 by Materials Project

Ba5Ca2Nb3O15 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded to twelve O atoms to form BaO12 cuboctahedra that share corners with twelve equivalent BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with four equivalent CaO6 octahedra, and faces with four equivalent NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 3.01–3.12 Å. In the second Ba site, Ba is bonded to twelve O atoms to form BaO12 cuboctahedra that share corners with twelve BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with three equivalent CaO6 octahedra, and faces with five NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.94–3.15 Å. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six NbO6 octahedra and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Ca–O bond distances ranging from 2.28–2.32 Å. There are three inequivalent Nb sites. In the first Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.02 Å) and two longer (2.10 Å) Nb–O bond lengths. In the second Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with five equivalent CaO6 octahedra, and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Nb–O bond distances ranging from 1.92–2.36 Å. In the third Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent CaO6 octahedra, and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.98 Å) and two longer (2.16 Å) Nb–O bond lengths. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted linear geometry to four Ba, one Ca, and one Nb atom. In the second O site, O is bonded in a distorted linear geometry to four equivalent Ba and two Nb atoms. In the third O site, O is bonded in a distorted linear geometry to four equivalent Ba, one Ca, and one Nb atom. In the fourth O site, O is bonded to four equivalent Ba and two Nb atoms to form a mixture of distorted corner and face-sharing OBa4Nb2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O site, O is bonded in a distorted linear geometry to four equivalent Ba, one Ca, and one Nb atom. In the sixth O site, O is bonded in a distorted linear geometry to four Ba, one Ca, and one Nb atom. In the seventh O site, O is bonded in a distorted linear geometry to four Ba, one Ca, and one Nb atom.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Back to Basics: Lanthanide and Heavy Actinide Chelation at High pH by Niobium Polyoxometalates

Niobium polyoxometalates (Nb-POMs) form in alkaline media, which limits their use as ligands for acidic cations, particularly lanthanides and actinides. Metal-Nb-POM moieties have the potential for emergent and enhanced properties, based on strong complexation behavior and high stability of the resultant materials. Here, in this study, we probe interactions of lanthanides (Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ , Tb 3+ , Dy 3+ ) and actinides (Am 3+ , Cm 3+ ) with a Nb-POM [Nb 6 O 19 ] 8– (Nb 6 ) in alkaline media. Nb 6 , the most charge-dense Nb-POM, enhances f-element luminescence emission by up to × 10 6 , via Nb-POM-mediated sensitization. Lengthened emission lifetimes correlate with the release of the metal-cation hydration sphere, replaced by multidentate Nb-POMs. The Nb 6 –Ln(An) complexes resist carbonate and phosphate displacement, and Nb 6 –Ln(An) complexation is retained upon isolation of the solids from solution. Electrospray ionization mass spectrometry (ESI-MS) and Raman spectroscopy both indicate the formation of the unprecedented Peacock–Weakley Nb-POM ([LnIII(Nb 5 O 18 ) 2 ] 19- ) in addition to simple Nb 6 –Ln coordination complexes. Luminescence emission spectra support the presence of simple Nb 6 –Ln coordination complexes. Small-angle X-ray scattering (SAXS) evidence the formation of Ln-Nb-POM aggregates. This foundational investigation highlights the potential of Nb-POMs as metal–ligands at basic pH, with value-added properties including scaffolding extended materials and controlling light absorption and emission.

organic↗
DOE OSTI2020

Materials Data on EuNb8O14 by Materials Project

EuNb8O14 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Eu2+ is bonded to twelve O2- atoms to form EuO12 cuboctahedra that share corners with two equivalent EuO12 cuboctahedra, corners with four equivalent NbO5 square pyramids, edges with six NbO5 square pyramids, faces with four equivalent NbO6 octahedra, and faces with two equivalent NbO5 square pyramids. There are a spread of Eu–O bond distances ranging from 2.69–3.01 Å. There are three inequivalent Nb+3.25+ sites. In the first Nb+3.25+ site, Nb+3.25+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with six NbO5 square pyramids, edges with two equivalent NbO5 square pyramids, and faces with two equivalent EuO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Nb–O bond distances ranging from 1.98–2.09 Å. In the second Nb+3.25+ site, Nb+3.25+ is bonded to five O2- atoms to form NbO5 square pyramids that share corners with four equivalent NbO6 octahedra, corners with six equivalent NbO5 square pyramids, an edgeedge with one EuO12 cuboctahedra, and a faceface with one EuO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–46°. There are a spread of Nb–O bond distances ranging from 2.10–2.21 Å. In the third Nb+3.25+ site, Nb+3.25+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one EuO12 cuboctahedra, a cornercorner with one NbO6 octahedra, corners with six NbO5 square pyramids, an edgeedge with one EuO12 cuboctahedra, an edgeedge with one NbO6 octahedra, and an edgeedge with one NbO5 square pyramid. The corner-sharing octahedral tilt angles are 48°. There are a spread of Nb–O bond distances ranging from 2.06–2.19 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Eu2+ and two equivalent Nb+3.25+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three Nb+3.25+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Eu2+ and three Nb+3.25+ atoms. In the fourth O2- site, O2- is bonded in a square co-planar geometry to four equivalent Nb+3.25+ atoms. In the fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Eu2+ and three Nb+3.25+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Eu2+ and three Nb+3.25+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaNb8O14 by Materials Project

BaNb8O14 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with two equivalent BaO12 cuboctahedra, corners with four equivalent NbO5 square pyramids, edges with six NbO5 square pyramids, faces with four equivalent NbO6 octahedra, and faces with two equivalent NbO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.83–3.01 Å. There are three inequivalent Nb+3.25+ sites. In the first Nb+3.25+ site, Nb+3.25+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with six NbO5 square pyramids, edges with two equivalent NbO5 square pyramids, and faces with two equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Nb–O bond distances ranging from 1.97–2.09 Å. In the second Nb+3.25+ site, Nb+3.25+ is bonded to five O2- atoms to form NbO5 square pyramids that share corners with four equivalent NbO6 octahedra, corners with six equivalent NbO5 square pyramids, an edgeedge with one BaO12 cuboctahedra, and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–45°. There are a spread of Nb–O bond distances ranging from 2.11–2.21 Å. In the third Nb+3.25+ site, Nb+3.25+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one BaO12 cuboctahedra, a cornercorner with one NbO6 octahedra, corners with six NbO5 square pyramids, an edgeedge with one BaO12 cuboctahedra, an edgeedge with one NbO6 octahedra, and an edgeedge with one NbO5 square pyramid. The corner-sharing octahedral tilt angles are 47°. There are a spread of Nb–O bond distances ranging from 2.05–2.19 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+ and two equivalent Nb+3.25+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three Nb+3.25+ atoms. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ba2+ and three Nb+3.25+ atoms. In the fourth O2- site, O2- is bonded in a square co-planar geometry to four equivalent Nb+3.25+ atoms. In the fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ba2+ and three Nb+3.25+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+ and three Nb+3.25+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KNb8O14 by Materials Project

KNb8O14 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share corners with two equivalent KO12 cuboctahedra, corners with four equivalent NbO5 square pyramids, edges with six NbO5 square pyramids, faces with four equivalent NbO6 octahedra, and faces with two equivalent NbO5 square pyramids. There are a spread of K–O bond distances ranging from 2.85–2.99 Å. There are three inequivalent Nb+3.38+ sites. In the first Nb+3.38+ site, Nb+3.38+ is bonded to five O2- atoms to form NbO5 square pyramids that share corners with four equivalent NbO6 octahedra, corners with six equivalent NbO5 square pyramids, an edgeedge with one KO12 cuboctahedra, and a faceface with one KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–43°. There are a spread of Nb–O bond distances ranging from 2.11–2.19 Å. In the second Nb+3.38+ site, Nb+3.38+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with six NbO5 square pyramids, edges with two equivalent NbO5 square pyramids, and faces with two equivalent KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Nb–O bond distances ranging from 2.00–2.09 Å. In the third Nb+3.38+ site, Nb+3.38+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one KO12 cuboctahedra, a cornercorner with one NbO6 octahedra, corners with six NbO5 square pyramids, an edgeedge with one KO12 cuboctahedra, an edgeedge with one NbO6 octahedra, and an edgeedge with one NbO5 square pyramid. The corner-sharing octahedral tilt angles are 47°. There are a spread of Nb–O bond distances ranging from 2.03–2.16 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to three Nb+3.38+ atoms. In the second O2- site, O2- is bonded in a square co-planar geometry to four equivalent Nb+3.38+ atoms. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to one K1+ and three Nb+3.38+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent K1+ and two equivalent Nb+3.38+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one K1+ and three Nb+3.38+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one K1+ and three Nb+3.38+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiNb3Cl8 by Materials Project

LiNb3Cl8 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. Li1+ is bonded to five Cl1- atoms to form distorted LiCl5 trigonal bipyramids that share corners with four NbCl5 square pyramids, edges with two NbCl5 square pyramids, and an edgeedge with one LiCl5 trigonal bipyramid. There are a spread of Li–Cl bond distances ranging from 2.35–2.82 Å. There are three inequivalent Nb+2.33+ sites. In the first Nb+2.33+ site, Nb+2.33+ is bonded to five Cl1- atoms to form NbCl5 square pyramids that share corners with five NbCl5 square pyramids, a cornercorner with one LiCl5 trigonal bipyramid, and an edgeedge with one LiCl5 trigonal bipyramid. There are a spread of Nb–Cl bond distances ranging from 2.46–2.81 Å. In the second Nb+2.33+ site, Nb+2.33+ is bonded to five Cl1- atoms to form NbCl5 square pyramids that share corners with four NbCl5 square pyramids and corners with two equivalent LiCl5 trigonal bipyramids. There are a spread of Nb–Cl bond distances ranging from 2.46–2.68 Å. In the third Nb+2.33+ site, Nb+2.33+ is bonded to five Cl1- atoms to form NbCl5 square pyramids that share corners with five NbCl5 square pyramids, a cornercorner with one LiCl5 trigonal bipyramid, and an edgeedge with one LiCl5 trigonal bipyramid. There are a spread of Nb–Cl bond distances ranging from 2.46–2.79 Å. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.33+ atoms. In the second Cl1- site, Cl1- is bonded in a 3-coordinate geometry to two equivalent Li1+ and one Nb+2.33+ atom. In the third Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one Li1+ and two Nb+2.33+ atoms. In the fourth Cl1- site, Cl1- is bonded in a distorted T-shaped geometry to one Li1+ and two Nb+2.33+ atoms. In the fifth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Nb+2.33+ atoms. In the sixth Cl1- site, Cl1- is bonded in a distorted T-shaped geometry to one Li1+ and two Nb+2.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4Te12I by Materials Project

Nb4Te12I crystallizes in the monoclinic C2/c space group. The structure is one-dimensional and consists of four Nb4Te12I ribbons oriented in the (0, 1, 0) direction. there are two inequivalent Nb+4.75+ sites. In the first Nb+4.75+ site, Nb+4.75+ is bonded to five Te+1.50- and one I1- atom to form a mixture of corner and edge-sharing NbTe5I pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.65–2.93 Å. The Nb–I bond length is 3.01 Å. In the second Nb+4.75+ site, Nb+4.75+ is bonded to five Te+1.50- and one I1- atom to form a mixture of corner and edge-sharing NbTe5I pentagonal pyramids. There are a spread of Nb–Te bond distances ranging from 2.65–2.95 Å. The Nb–I bond length is 3.00 Å. There are six inequivalent Te+1.50- sites. In the first Te+1.50- site, Te+1.50- is bonded in a single-bond geometry to one Nb+4.75+ atom. In the second Te+1.50- site, Te+1.50- is bonded in a 2-coordinate geometry to two Nb+4.75+ atoms. In the third Te+1.50- site, Te+1.50- is bonded in a single-bond geometry to one Nb+4.75+ atom. In the fourth Te+1.50- site, Te+1.50- is bonded in a 2-coordinate geometry to two Nb+4.75+ atoms. In the fifth Te+1.50- site, Te+1.50- is bonded in a 2-coordinate geometry to two Nb+4.75+ atoms. In the sixth Te+1.50- site, Te+1.50- is bonded in a 2-coordinate geometry to two Nb+4.75+ atoms. I1- is bonded in a 4-coordinate geometry to four Nb+4.75+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3B3C by Materials Project

Nb3B3C crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are three inequivalent Nb+2.33+ sites. In the first Nb+2.33+ site, Nb+2.33+ is bonded to twelve B1- atoms to form NbB12 cuboctahedra that share corners with two equivalent NbBC5 square pyramids, edges with eight equivalent NbB12 cuboctahedra, and faces with six equivalent NbB12 cuboctahedra. There are a spread of Nb–B bond distances ranging from 2.43–2.50 Å. In the second Nb+2.33+ site, Nb+2.33+ is bonded to one B1- and five equivalent C4- atoms to form distorted NbBC5 square pyramids that share corners with two equivalent NbB12 cuboctahedra, corners with four equivalent NbBC5 square pyramids, and edges with eight equivalent NbBC5 square pyramids. The Nb–B bond length is 2.90 Å. There are one shorter (2.17 Å) and four longer (2.27 Å) Nb–C bond lengths. In the third Nb+2.33+ site, Nb+2.33+ is bonded in a 1-coordinate geometry to six B1- and one C4- atom. There are two shorter (2.36 Å) and four longer (2.39 Å) Nb–B bond lengths. The Nb–C bond length is 2.15 Å. There are three inequivalent B1- sites. In the first B1- site, B1- is bonded in a 9-coordinate geometry to six equivalent Nb+2.33+ and three B1- atoms. There is two shorter (1.81 Å) and one longer (1.84 Å) B–B bond length. In the second B1- site, B1- is bonded in a 9-coordinate geometry to seven Nb+2.33+ and two equivalent B1- atoms. Both B–B bond lengths are 1.84 Å. In the third B1- site, B1- is bonded in a 9-coordinate geometry to six Nb+2.33+ and three B1- atoms. C4- is bonded to six Nb+2.33+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°.

36 MATERIALS SCIENCE↗