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Materials Data on Nb4FeS8 by Materials Project

Nb4FeS8 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of two Nb4FeS8 sheets oriented in the (1, 0, 0) direction. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with four equivalent FeS6 octahedra and edges with six NbS6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 48–49°. There are a spread of Nb–S bond distances ranging from 2.49–2.53 Å. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with two equivalent FeS6 octahedra, edges with six NbS6 pentagonal pyramids, and a faceface with one FeS6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Nb–S bond distances ranging from 2.45–2.53 Å. Fe2+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with twelve NbS6 pentagonal pyramids, edges with two equivalent FeS6 octahedra, and faces with two equivalent NbS6 pentagonal pyramids. There are two shorter (2.28 Å) and four longer (2.31 Å) Fe–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three Nb+3.50+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three Nb+3.50+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to three Nb+3.50+ and two equivalent Fe2+ atoms. In the fourth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.50+ and one Fe2+ atom.

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Materials Data on AcNb3 by Materials Project

AcNb3 is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ac is bonded in a distorted body-centered cubic geometry to fourteen Nb atoms. There are eight shorter (3.06 Å) and six longer (3.53 Å) Ac–Nb bond lengths. There are two inequivalent Nb sites. In the first Nb site, Nb is bonded to four equivalent Ac and four equivalent Nb atoms to form a mixture of distorted face, edge, and corner-sharing NbAc4Nb4 tetrahedra. All Nb–Nb bond lengths are 3.06 Å. In the second Nb site, Nb is bonded in a 8-coordinate geometry to six equivalent Ac and eight equivalent Nb atoms.

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Materials Data on Nb6InSe8 by Materials Project

Nb6InSe8 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are two inequivalent Nb+2.50+ sites. In the first Nb+2.50+ site, Nb+2.50+ is bonded to six Se2- atoms to form a mixture of distorted edge, face, and corner-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.84 Å. In the second Nb+2.50+ site, Nb+2.50+ is bonded to six Se2- atoms to form a mixture of distorted edge, face, and corner-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.85 Å. In1+ is bonded in a trigonal planar geometry to three equivalent Se2- atoms. All In–Se bond lengths are 3.22 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six equivalent Nb+2.50+ atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se2- site, Se2- is bonded to six equivalent Nb+2.50+ atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to four Nb+2.50+ and one In1+ atom. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Nb+2.50+ atoms.

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Materials Data on NbRh2 by Materials Project

NbRh2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a 12-coordinate geometry to nine Rh atoms. There are a spread of Nb–Rh bond distances ranging from 2.70–2.82 Å. In the second Nb site, Nb is bonded in a 9-coordinate geometry to nine Rh atoms. There are a spread of Nb–Rh bond distances ranging from 2.68–2.86 Å. There are four inequivalent Rh sites. In the first Rh site, Rh is bonded to six Nb atoms to form a mixture of distorted edge, corner, and face-sharing RhNb6 cuboctahedra. In the second Rh site, Rh is bonded to four Nb atoms to form a mixture of distorted edge and corner-sharing RhNb4 cuboctahedra. In the third Rh site, Rh is bonded to six Nb atoms to form distorted RhNb6 cuboctahedra that share corners with ten RhNb4 cuboctahedra, edges with nine RhNb6 cuboctahedra, and faces with four RhNb6 cuboctahedra. In the fourth Rh site, Rh is bonded in a distorted water-like geometry to two Nb atoms.

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Materials Data on Nb4AlN3 by Materials Project

Nb4AlN3 is MAX Phase 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 six N atoms to form a mixture of corner and edge-sharing NbN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.19 Å) and three longer (2.25 Å) Nb–N bond lengths. In the second Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent N atoms. All Nb–Al bond lengths are 2.85 Å. All Nb–N bond lengths are 2.20 Å. Al is bonded to six equivalent Nb atoms to form distorted AlNb6 cuboctahedra that share corners with six equivalent NNb6 octahedra, edges with six equivalent AlNb6 cuboctahedra, and edges with six equivalent NNb6 octahedra. The corner-sharing octahedral tilt angles are 16°. There are two inequivalent N sites. In the first N site, N is bonded to six equivalent Nb atoms to form a mixture of corner and edge-sharing NNb6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second N site, N is bonded to six Nb atoms to form NNb6 octahedra that share corners with three equivalent AlNb6 cuboctahedra, corners with three equivalent NNb6 octahedra, edges with three equivalent AlNb6 cuboctahedra, and edges with nine NNb6 octahedra. The corner-sharing octahedral tilt angles are 2°.

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Materials Data on Nb2FeS4 by Materials Project

FeNb2S4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Nb+2.50+ sites. In the first Nb+2.50+ site, Nb+2.50+ is bonded to six S2- atoms to form NbS6 octahedra that share corners with three equivalent NbS7 pentagonal bipyramids, edges with four equivalent NbS6 octahedra, and edges with two equivalent NbS7 pentagonal bipyramids. There are a spread of Nb–S bond distances ranging from 2.49–2.63 Å. In the second Nb+2.50+ site, Nb+2.50+ is bonded to seven S2- atoms to form distorted NbS7 pentagonal bipyramids that share corners with three equivalent NbS6 octahedra, edges with two equivalent NbS6 octahedra, and edges with four equivalent NbS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–42°. There are a spread of Nb–S bond distances ranging from 2.52–2.72 Å. Fe3+ is bonded in a 5-coordinate geometry to seven S2- atoms. There are a spread of Fe–S bond distances ranging from 2.31–3.08 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to four Nb+2.50+ and two equivalent Fe3+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three Nb+2.50+ and two equivalent Fe3+ atoms. In the third S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Nb+2.50+ and two equivalent Fe3+ atoms. In the fourth S2- site, S2- is bonded to three Nb+2.50+ and one Fe3+ atom to form distorted corner-sharing SNb3Fe trigonal pyramids.

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Materials Data on NaNb4(PO4)6 by Materials Project

NaNb4(PO4)6 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Na1+ is bonded in a distorted hexagonal planar geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.53 Å. There are two inequivalent Nb+4.25+ sites. In the first Nb+4.25+ site, Nb+4.25+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are three shorter (2.02 Å) and three longer (2.09 Å) Nb–O bond lengths. In the second Nb+4.25+ site, Nb+4.25+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are three shorter (2.02 Å) and three longer (2.03 Å) Nb–O bond lengths. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four NbO6 octahedra. The corner-sharing octahedra tilt angles range from 22–36°. There is three shorter (1.54 Å) and one longer (1.55 Å) P–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb+4.25+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb+4.25+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Nb+4.25+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb+4.25+ and one P5+ atom.

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Materials Data on Nb3Co5B2 by Materials Project

Nb3Co5B2 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 1-coordinate geometry to ten Co and three equivalent B atoms. There are a spread of Nb–Co bond distances ranging from 2.65–2.77 Å. There are one shorter (2.47 Å) and two longer (2.52 Å) Nb–B bond lengths. In the second Nb site, Nb is bonded in a body-centered cubic geometry to eight equivalent Co atoms. All Nb–Co bond lengths are 2.54 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to four equivalent Nb, four equivalent Co, and four equivalent B atoms. All Co–Co bond lengths are 2.43 Å. All Co–B bond lengths are 2.15 Å. In the second Co site, Co is bonded in a 4-coordinate geometry to six Nb, four Co, and two equivalent B atoms. There are one shorter (2.50 Å) and two longer (2.77 Å) Co–Co bond lengths. Both Co–B bond lengths are 2.16 Å. B is bonded in a 9-coordinate geometry to three equivalent Nb and six Co atoms.

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Materials Data on Nb2AgS4 by Materials Project

Nb2AgS4 crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one Nb2AgS4 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. There are three shorter (2.48 Å) and three longer (2.52 Å) Nb–S bond lengths. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. There are three shorter (2.48 Å) and three longer (2.51 Å) Nb–S bond lengths. Ag1+ is bonded in a 4-coordinate geometry to four S2- atoms. There are one shorter (2.44 Å) and three longer (2.71 Å) Ag–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to three equivalent Nb+3.50+ and one Ag1+ atom. In the second S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Nb+3.50+ and three equivalent Ag1+ atoms. In the third S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Nb+3.50+ atoms. In the fourth S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Nb+3.50+ atoms.

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Materials Data on Nb2CuTe4 by Materials Project

Nb2CuTe4 crystallizes in the monoclinic Pm 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 Te2- atoms to form distorted NbTe6 octahedra that share corners with three equivalent CuTe4 tetrahedra, edges with six NbTe6 octahedra, and a faceface with one CuTe4 tetrahedra. There are a spread of Nb–Te bond distances ranging from 2.78–3.00 Å. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six Te2- atoms to form distorted NbTe6 octahedra that share corners with six equivalent CuTe4 tetrahedra and edges with six NbTe6 octahedra. There are a spread of Nb–Te bond distances ranging from 2.75–2.96 Å. Cu1+ is bonded to four Te2- atoms to form CuTe4 tetrahedra that share corners with nine NbTe6 octahedra, corners with two equivalent CuTe4 tetrahedra, and a faceface with one NbTe6 octahedra. The corner-sharing octahedra tilt angles range from 49–63°. There are a spread of Cu–Te bond distances ranging from 2.58–2.62 Å. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 4-coordinate geometry to three Nb+3.50+ and one Cu1+ atom. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three Nb+3.50+ atoms. In the third Te2- site, Te2- is bonded to three Nb+3.50+ and one Cu1+ atom to form distorted corner-sharing TeNb3Cu tetrahedra. In the fourth Te2- site, Te2- is bonded in a 5-coordinate geometry to three Nb+3.50+ and two equivalent Cu1+ atoms.

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Materials Data on Nb2CuS4 by Materials Project

Nb2CuS4 crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one Nb2CuS4 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. There are three shorter (2.48 Å) and three longer (2.53 Å) Nb–S bond lengths. In the second Nb+3.50+ site, Nb+3.50+ is bonded to six S2- atoms to form distorted edge-sharing NbS6 pentagonal pyramids. There are three shorter (2.47 Å) and three longer (2.51 Å) Nb–S bond lengths. Cu1+ is bonded in a distorted rectangular see-saw-like geometry to four S2- atoms. There are one shorter (2.21 Å) and three longer (2.33 Å) Cu–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Nb+3.50+ and one Cu1+ atom. In the second S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Nb+3.50+ and three equivalent Cu1+ atoms. In the third S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Nb+3.50+ atoms. In the fourth S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Nb+3.50+ atoms.

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Materials Data on K2(NbSe2)3 by Materials Project

K2(NbSe2)3 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six Se2- atoms. All K–Se bond lengths are 3.27 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six Se2- atoms. All K–Se bond lengths are 3.27 Å. There are two inequivalent Nb+3.33+ sites. In the first Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted edge-sharing NbSe6 pentagonal pyramids. There are two shorter (2.63 Å) and four longer (2.64 Å) Nb–Se bond lengths. In the second Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted edge-sharing NbSe6 pentagonal pyramids. There are a spread of Nb–Se bond distances ranging from 2.62–2.64 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent K1+ and three Nb+3.33+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent K1+ and three Nb+3.33+ atoms. In the third Se2- site, Se2- is bonded to two equivalent K1+ and three Nb+3.33+ atoms to form a mixture of distorted edge and corner-sharing SeK2Nb3 square pyramids. In the fourth Se2- site, Se2- is bonded to two equivalent K1+ and three Nb+3.33+ atoms to form a mixture of distorted edge and corner-sharing SeK2Nb3 square pyramids.

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The lattice parameter – composition relationship of the body centered cubic uranium-niobium alloys

In this paper, in-situ time-of-flight neutron diffraction experiments were performed on uranium-niobium alloy with 6 wt% Nb to study the lattice parameter-composition relationship for the body centered cubic (bcc) alloys. Based on lattice-parameter measurements of Nb-supersaturated γs phase over the range of 450 – 790 °C, an improved Vegard's-type relationship was established for determination of Nb concentrations at elevated temperatures. Neutron diffraction data were also collected as a function of aging time over the 450 - 600 °C range when γs phase decomposed isothermally into the mixture of orthorhombic α-U and Nb-rich bcc phase, as well as at room-temperature on the alloys aged ex-situ at 500 °C up to five years. From these measurements, the average Nb concentrations in the bcc phase were determined based on the Rietveld refinements of weight fraction and mass conservation relations (lever rule). Over the 15at% – 78at% range of Nb concentrations that correspond to different experimental aging times, the lattice parameters at constant temperatures exhibit a nonlinear S-shaped variation with Nb concentration, and the associated excess volumes of mixing can be described by a subregular solution model of the Redlich–Kister type of polynomial. Over the full range of composition the S-shaped deviation from Vegard's law can be modeled using a combination of an elastic continuum model and a perturbation to the radii of the solute atoms in the solvent, suggesting that electronic interactions between solute and solvent atoms could play an important role in the compositional dependence of lattice parameter for the γ-phase U-Nb alloys. While Vegard's law is a straightforward and reasonably good approximation for the bcc solid solutions in the U-Nb system, the Nb concentrations determined from the weight fraction refinements of diffraction data provide internally consistent, mass-conserving estimates of solute redistribution for the monotectoid reaction.

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Materials Data on Nb5(PPd)4 by Materials Project

Nb5Pd4P4 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 4-coordinate geometry to four equivalent Pd and five equivalent P atoms. There are a spread of Nb–Pd bond distances ranging from 2.90–3.07 Å. There are a spread of Nb–P bond distances ranging from 2.59–3.00 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 2.62 Å. Pd is bonded in a 12-coordinate geometry to four equivalent Nb, five equivalent Pd, and three equivalent P atoms. There are four shorter (2.87 Å) and one longer (3.14 Å) Pd–Pd bond lengths. There are two shorter (2.38 Å) and one longer (2.49 Å) Pd–P bond lengths. P is bonded in a 9-coordinate geometry to six Nb and three equivalent Pd atoms.

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Materials Data on U2Nb3Ge4 by Materials Project

U2Nb3Ge4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. U is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of U–Ge bond distances ranging from 2.87–3.03 Å. There are two inequivalent Nb sites. In the first Nb site, Nb is bonded to six Ge atoms to form corner-sharing NbGe6 octahedra. The corner-sharing octahedra tilt angles range from 47–53°. There are a spread of Nb–Ge bond distances ranging from 2.74–2.82 Å. In the second Nb site, Nb is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Nb–Ge bond distances ranging from 2.64–2.80 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent U, four Nb, and one Ge atom. The Ge–Ge bond length is 2.68 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent U, six Nb, and one Ge atom. In the third Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent U, four Nb, and one Ge atom. The Ge–Ge bond length is 2.77 Å.

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Materials Data on Nb6C5 by Materials Project

Nb6C5 crystallizes in the monoclinic C2/m 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 five C4- atoms to form a mixture of edge and corner-sharing NbC5 square pyramids. There are a spread of Nb–C bond distances ranging from 2.12–2.25 Å. In the second Nb+3.33+ site, Nb+3.33+ is bonded to five C4- atoms to form a mixture of edge and corner-sharing NbC5 square pyramids. There are a spread of Nb–C bond distances ranging from 2.15–2.29 Å. There are three inequivalent C4- sites. In the first C4- site, C4- is bonded to six Nb+3.33+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the second C4- site, C4- is bonded to six Nb+3.33+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedra tilt angles range from 5–7°. In the third C4- site, C4- is bonded to six Nb+3.33+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedra tilt angles range from 6–7°.

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Materials Data on BaNb4O6 by Materials Project

BaNb4O6 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, and faces with eight equivalent NbO5 square pyramids. There are eight shorter (2.93 Å) and four longer (3.00 Å) Ba–O bond lengths. There are two inequivalent Nb+2.50+ sites. In the first Nb+2.50+ site, Nb+2.50+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.12 Å) and two longer (2.13 Å) Nb–O bond lengths. In the second Nb+2.50+ site, Nb+2.50+ is bonded to five O2- atoms to form NbO5 square pyramids that share corners with five equivalent NbO5 square pyramids and faces with four equivalent BaO12 cuboctahedra. There are one shorter (2.10 Å) and four longer (2.12 Å) Nb–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Nb+2.50+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and three Nb+2.50+ atoms. In the third O2- site, O2- is bonded in a square co-planar geometry to four equivalent Nb+2.50+ atoms.

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Materials Data on Nb4Zn2C by Materials Project

Nb4Zn2C crystallizes in the cubic Fd-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 bent 150 degrees geometry to four equivalent Zn and two equivalent C atoms. There are two shorter (2.74 Å) and two longer (3.04 Å) Nb–Zn bond lengths. Both Nb–C bond lengths are 2.25 Å. In the second Nb site, Nb is bonded to six equivalent Zn atoms to form distorted edge-sharing NbZn6 cuboctahedra. All Nb–Zn bond lengths are 2.63 Å. Zn is bonded in a 12-coordinate geometry to nine Nb and three equivalent Zn atoms. All Zn–Zn bond lengths are 3.02 Å. C is bonded to six equivalent Nb atoms to form corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 40°.

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