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DOE OSTI2020

Materials Data on NaTaWO7 by Materials Project

NaTaWO7 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Na is bonded to eight O atoms to form NaO8 hexagonal bipyramids that share edges with two equivalent NaO8 hexagonal bipyramids, edges with two equivalent WO6 octahedra, and edges with four equivalent TaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.40–2.70 Å. Ta is bonded to six O atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra, corners with four equivalent WO6 octahedra, and edges with four equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–41°. There is two shorter (1.97 Å) and four longer (2.00 Å) Ta–O bond length. W is bonded to six O atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four equivalent TaO6 octahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 35–38°. All W–O bond lengths are 1.94 Å. There are four inequivalent O sites. In the first O site, O is bonded in a water-like geometry to two equivalent Na atoms. In the second O site, O is bonded in a 3-coordinate geometry to one Na, one Ta, and one W atom. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the fourth O site, O is bonded in a 4-coordinate geometry to two equivalent Na and two equivalent Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaZrTa3O11 by Materials Project

LaZrTa3O11 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.44–2.63 Å. In the second La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.46–2.63 Å. Zr4+ is bonded to seven O2- atoms to form distorted ZrO7 pentagonal bipyramids that share corners with two TaO6 octahedra. The corner-sharing octahedra tilt angles range from 46–47°. There are a spread of Zr–O bond distances ranging from 2.08–2.51 Å. There are four inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ta–O bond distances ranging from 1.94–2.51 Å. In the second Ta5+ site, Ta5+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ta–O bond distances ranging from 1.94–2.52 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent ZrO7 pentagonal bipyramids. There are a spread of Ta–O bond distances ranging from 1.95–2.04 Å. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent ZrO7 pentagonal bipyramids. There are a spread of Ta–O bond distances ranging from 1.98–2.02 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one La3+, one Zr4+, and two Ta5+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one La3+, one Zr4+, and two Ta5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Zr4+ and two Ta5+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Zr4+ and two Ta5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Zr4+ and two Ta5+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Ta5+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Ta5+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one La3+, one Zr4+, and one Ta5+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+, one Zr4+, and one Ta5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Ta5+ atoms. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Ta5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaTaNO2 by Materials Project

CaTaO2N is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to three equivalent N3- and five O2- atoms. There are a spread of Ca–N bond distances ranging from 2.42–2.76 Å. There are a spread of Ca–O bond distances ranging from 2.39–2.87 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to two equivalent N3- and four O2- atoms to form corner-sharing TaN2O4 octahedra. The corner-sharing octahedra tilt angles range from 26–29°. Both Ta–N bond lengths are 2.04 Å. There are two shorter (2.04 Å) and two longer (2.06 Å) Ta–O bond lengths. In the second Ta5+ site, Ta5+ is bonded to two equivalent N3- and four O2- atoms to form corner-sharing TaN2O4 octahedra. The corner-sharing octahedra tilt angles range from 26–29°. Both Ta–N bond lengths are 2.04 Å. There are two shorter (2.04 Å) and two longer (2.05 Å) Ta–O bond lengths. N3- is bonded in a 5-coordinate geometry to three equivalent Ca2+ and two Ta5+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two Ta5+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Ca2+ and two Ta5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta5N10Cl17 by Materials Project

Ta5N10Cl17 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. there are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to two equivalent N+0.80- and four Cl1- atoms to form corner-sharing TaN2Cl4 octahedra. The corner-sharing octahedral tilt angles are 27°. Both Ta–N bond lengths are 2.11 Å. There are a spread of Ta–Cl bond distances ranging from 2.30–2.48 Å. In the second Ta5+ site, Ta5+ is bonded in a 5-coordinate geometry to four equivalent N+0.80- and one Cl1- atom. All Ta–N bond lengths are 2.08 Å. The Ta–Cl bond length is 2.37 Å. There are three inequivalent N+0.80- sites. In the first N+0.80- site, N+0.80- is bonded in a distorted T-shaped geometry to three Ta5+ atoms. In the second N+0.80- site, N+0.80- is bonded in a body-centered cubic geometry to eight Cl1- atoms. There are a spread of N–Cl bond distances ranging from 3.23–3.34 Å. In the third N+0.80- site, N+0.80- is bonded in a distorted linear geometry to two equivalent Cl1- atoms. Both N–Cl bond lengths are 3.64 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ and two equivalent N+0.80- atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ and two equivalent N+0.80- atoms. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Ta5+ and three N+0.80- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaGaNi6 by Materials Project

TaNi6Ga is beta Cu3Ti-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ta is bonded to twelve Ni atoms to form TaNi12 cuboctahedra that share corners with four equivalent TaNi12 cuboctahedra, corners with eight equivalent GaNi12 cuboctahedra, edges with twenty-four NiGa4Ni8 cuboctahedra, faces with two equivalent GaNi12 cuboctahedra, faces with four equivalent TaNi12 cuboctahedra, and faces with twelve NiTa4Ni8 cuboctahedra. All Ta–Ni bond lengths are 2.56 Å. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to eight equivalent Ni and four equivalent Ga atoms to form NiGa4Ni8 cuboctahedra that share corners with twelve NiGa4Ni8 cuboctahedra, edges with eight equivalent TaNi12 cuboctahedra, edges with sixteen equivalent NiTa2Ga2Ni8 cuboctahedra, faces with four equivalent GaNi12 cuboctahedra, and faces with fourteen NiGa4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.55 Å. All Ni–Ga bond lengths are 2.56 Å. In the second Ni site, Ni is bonded to four equivalent Ta and eight equivalent Ni atoms to form distorted NiTa4Ni8 cuboctahedra that share corners with twelve NiGa4Ni8 cuboctahedra, edges with eight equivalent GaNi12 cuboctahedra, edges with sixteen equivalent NiTa2Ga2Ni8 cuboctahedra, faces with four equivalent TaNi12 cuboctahedra, and faces with fourteen NiGa4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.56 Å. In the third Ni site, Ni is bonded to two equivalent Ta, eight Ni, and two equivalent Ga atoms to form distorted NiTa2Ga2Ni8 cuboctahedra that share corners with twelve equivalent NiTa2Ga2Ni8 cuboctahedra, edges with four equivalent TaNi12 cuboctahedra, edges with four equivalent GaNi12 cuboctahedra, edges with sixteen NiGa4Ni8 cuboctahedra, faces with two equivalent TaNi12 cuboctahedra, faces with two equivalent GaNi12 cuboctahedra, and faces with fourteen NiGa4Ni8 cuboctahedra. All Ni–Ni bond lengths are 2.56 Å. Both Ni–Ga bond lengths are 2.55 Å. Ga is bonded to twelve Ni atoms to form GaNi12 cuboctahedra that share corners with four equivalent GaNi12 cuboctahedra, corners with eight equivalent TaNi12 cuboctahedra, edges with twenty-four NiTa4Ni8 cuboctahedra, faces with two equivalent TaNi12 cuboctahedra, faces with four equivalent GaNi12 cuboctahedra, and faces with twelve NiGa4Ni8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaMnSi by Materials Project

TaMnSi crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Ta is bonded in a 5-coordinate geometry to five Si atoms. There are four shorter (2.60 Å) and one longer (2.63 Å) Ta–Si bond lengths. Mn is bonded in a 4-coordinate geometry to four Si atoms. There are two shorter (2.35 Å) and two longer (2.46 Å) Mn–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to three equivalent Ta and six equivalent Mn atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to six equivalent Ta and three equivalent Mn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta2AgS4 by Materials Project

Ta2AgS4 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Ta2AgS4 sheet oriented in the (0, 0, 1) direction. Ta+3.50+ is bonded to six S2- atoms to form distorted edge-sharing TaS6 pentagonal pyramids. There are three shorter (2.47 Å) and three longer (2.51 Å) Ta–S bond lengths. Ag1+ is bonded in a 6-coordinate geometry to six equivalent S2- atoms. All Ag–S bond lengths are 2.81 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Ta+3.50+ and three equivalent Ag1+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Ta+3.50+ atoms.

36 MATERIALS SCIENCE↗
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Materials Data on TaWO7 by Materials Project

(TaWO6)2O2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional and consists of four water molecules and one TaWO6 framework. In the TaWO6 framework, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra and corners with four equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 37–38°. There is two shorter (1.97 Å) and four longer (1.99 Å) Ta–O bond length. W is bonded to six O atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra and corners with four equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–37°. There is four shorter (1.92 Å) and two longer (1.95 Å) W–O bond length. There are three inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two equivalent Ta atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the third O site, O is bonded in a bent 150 degrees geometry to one Ta and one W atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbTa7(CuO7)3 by Materials Project

RbTa7(CuO7)3 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to ten O2- atoms. There are a spread of Rb–O bond distances ranging from 3.22–3.54 Å. In the second Rb1+ site, Rb1+ is bonded to twelve O2- atoms to form distorted RbO12 cuboctahedra that share edges with twelve TaO6 octahedra. There are a spread of Rb–O bond distances ranging from 3.19–3.48 Å. There are four inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 34–48°. There are a spread of Ta–O bond distances ranging from 1.96–2.03 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with two equivalent RbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 10–34°. There are a spread of Ta–O bond distances ranging from 1.92–2.02 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one RbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 23–47°. There are a spread of Ta–O bond distances ranging from 1.90–2.15 Å. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one RbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 22–42°. There are a spread of Ta–O bond distances ranging from 1.90–2.13 Å. There are six inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.94 Å) and two longer (1.98 Å) Cu–O bond length. In the second Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to six O2- atoms. There are a spread of Cu–O bond distances ranging from 1.97–2.52 Å. In the third Cu2+ site, Cu2+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.98 Å. In the fourth Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Cu–O bond lengths are 2.11 Å. In the fifth Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.03 Å) and two longer (2.12 Å) Cu–O bond lengths. In the sixth Cu2+ site, Cu2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are two shorter (1.97 Å) and two longer (2.17 Å) Cu–O bond lengths. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Rb1+ and two equivalent Ta5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Rb1+ and two equivalent Ta5+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Ta5+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ta5+ and one Cu2+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Ta5+ and one Cu2+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ta5+ and one Cu2+ atom. In the seventh O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the ninth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Ta5+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Rb1+ and two Ta5+ atoms. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Rb1+ and two Ta5+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ta5+ and one Cu2+ atom. In the sixteenth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ta5+ and one Cu2+ atom. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ta5+ and two Cu2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfTaB2 by Materials Project

HfTaB2 is delta Molybdenum Boride-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Hf is bonded in a 7-coordinate geometry to seven B atoms. There are a spread of Hf–B bond distances ranging from 2.48–2.67 Å. Ta is bonded in a 7-coordinate geometry to seven B atoms. There are a spread of Ta–B bond distances ranging from 2.42–2.81 Å. There are two inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to three equivalent Hf, four equivalent Ta, and two equivalent B atoms. Both B–B bond lengths are 1.86 Å. In the second B site, B is bonded in a 9-coordinate geometry to four equivalent Hf, three equivalent Ta, and two equivalent B atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y7Ta3O18 by Materials Project

Y7Ta3O18 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are eight inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share a cornercorner with one TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, a cornercorner with one TaO7 pentagonal bipyramid, an edgeedge with one TaO6 octahedra, an edgeedge with one TaO7 pentagonal bipyramid, and edges with two YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 50°. There are a spread of Y–O bond distances ranging from 2.21–2.54 Å. In the second Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.27–2.64 Å. In the third Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, edges with two TaO6 octahedra, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 44–47°. There are a spread of Y–O bond distances ranging from 2.21–2.47 Å. In the fourth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, edges with two TaO6 octahedra, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 45–46°. There are a spread of Y–O bond distances ranging from 2.21–2.46 Å. In the fifth Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.31–2.62 Å. In the sixth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share a cornercorner with one TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, a cornercorner with one TaO7 pentagonal bipyramid, an edgeedge with one TaO6 octahedra, an edgeedge with one TaO7 pentagonal bipyramid, and edges with two YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are a spread of Y–O bond distances ranging from 2.22–2.55 Å. In the seventh Y3+ site, Y3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.25–2.65 Å. In the eighth Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.27–2.46 Å. There are four inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share a cornercorner with one TaO6 octahedra, a cornercorner with one TaO7 pentagonal bipyramid, corners with four YO7 pentagonal bipyramids, and edges with four YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are a spread of Ta–O bond distances ranging from 1.98–2.05 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra, corners with four YO7 pentagonal bipyramids, and edges with four YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are four shorter (1.99 Å) and two longer (2.02 Å) Ta–O bond lengths. In the third Ta5+ site, Ta5+ is bonded to seven O2- atoms to form distorted TaO7 pentagonal bipyramids that share a cornercorner with one TaO6 octahedra, corners with two YO7 pentagonal bipyramids, an edgeedge with one TaO7 pentagonal bipyramid, and edges with two YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. There are a spread of Ta–O bond distances ranging from 2.00–2.18 Å. In the fourth Ta5+ site, Ta5+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ta–O bond distances ranging from 2.01–2.40 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom. In the sixth O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the seventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ta5+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom. In the eleventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ta5+ atoms. In the thirteenth O2- site, O2- is bonded to three Y3+ and one Ta5+ atom to form OY3Ta tetrahedra that share corners with ten OY3Ta tetrahedra and edges with three OY4 tetrahedra. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ta5+ atoms. In the fifteenth O2- site, O2- is bonded to two Y3+ and two Ta5+ atoms to form distorted OY2Ta2 tetrahedra that share corners with seven OY3Ta tetrahedra and edges with three OY4 tetrahedra. In the sixteenth O2- site, O2- is bonded to three Y3+ and one Ta5+ atom to form distorted OY3Ta tetrahedra that share corners with eight OY4 tetrahedra and edges with four OY3Ta tetrahedra. In the seventeenth O2- site, O2- is bonded to one Y3+ and three Ta5+ atoms to form a mixture of distorted edge and corner-sharing OYTa3 tetrahedra. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaCo3 by Materials Project

Co3Ta is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ta is bonded to twelve Co atoms to form TaCo12 cuboctahedra that share corners with six equivalent TaCo12 cuboctahedra, corners with twelve CoTa4Co8 cuboctahedra, edges with eighteen CoTa4Co8 cuboctahedra, faces with eight equivalent TaCo12 cuboctahedra, and faces with twelve CoTa4Co8 cuboctahedra. There are six shorter (2.60 Å) and six longer (2.62 Å) Ta–Co bond lengths. There are two inequivalent Co sites. In the first Co site, Co is bonded to four equivalent Ta and eight equivalent Co atoms to form distorted CoTa4Co8 cuboctahedra that share corners with four equivalent TaCo12 cuboctahedra, corners with fourteen CoTa4Co8 cuboctahedra, edges with six equivalent TaCo12 cuboctahedra, edges with twelve equivalent CoTa4Co8 cuboctahedra, faces with four equivalent TaCo12 cuboctahedra, and faces with sixteen CoTa4Co8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.46–2.72 Å. In the second Co site, Co is bonded to four equivalent Ta and eight Co atoms to form distorted CoTa4Co8 cuboctahedra that share corners with four equivalent TaCo12 cuboctahedra, corners with fourteen CoTa4Co8 cuboctahedra, edges with six equivalent TaCo12 cuboctahedra, edges with twelve CoTa4Co8 cuboctahedra, faces with four equivalent TaCo12 cuboctahedra, and faces with sixteen CoTa4Co8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.46–2.72 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaTe4Cl4O by Materials Project

TaTeOCl4(Te)3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of twenty-four telloy molecules and two TaTeOCl4 clusters. In each TaTeOCl4 cluster, there are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to two O2- and four Cl1- atoms to form distorted corner-sharing TaCl4O2 octahedra. The corner-sharing octahedra tilt angles range from 3–11°. There is one shorter (1.89 Å) and one longer (1.93 Å) Ta–O bond length. There are a spread of Ta–Cl bond distances ranging from 2.36–2.54 Å. In the second Ta5+ site, Ta5+ is bonded to two O2- and four Cl1- atoms to form corner-sharing TaCl4O2 octahedra. The corner-sharing octahedra tilt angles range from 3–11°. There is one shorter (1.90 Å) and one longer (1.94 Å) Ta–O bond length. There are a spread of Ta–Cl bond distances ranging from 2.35–2.49 Å. There are two inequivalent Te+0.25+ sites. In the first Te+0.25+ site, Te+0.25+ is bonded in a single-bond geometry to one Cl1- atom. The Te–Cl bond length is 3.22 Å. In the second Te+0.25+ site, Te+0.25+ is bonded in a distorted single-bond geometry to one Cl1- atom. The Te–Cl bond length is 3.32 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. There are eight inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Ta5+ and one Te+0.25+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ and one Te+0.25+ atom. In the eighth Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KTaWO7 by Materials Project

(KTaWO6)2O2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional and consists of four water molecules and one KTaWO6 framework. In the KTaWO6 framework, K is bonded in a hexagonal planar geometry to six O atoms. There are two shorter (2.72 Å) and four longer (2.76 Å) K–O bond lengths. Ta is bonded to six O atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra and corners with four equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 37–38°. There is two shorter (1.99 Å) and four longer (2.00 Å) Ta–O bond length. W is bonded to six O atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra and corners with four equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–37°. There is four shorter (1.94 Å) and two longer (1.96 Å) W–O bond length. There are three inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to two equivalent K and two equivalent Ta atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the third O site, O is bonded in a 3-coordinate geometry to one K, one Ta, and one W atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaNbAl6 by Materials Project

TaNbAl6 is beta Cu3Ti-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ta is bonded to twelve Al atoms to form TaAl12 cuboctahedra that share corners with four equivalent TaAl12 cuboctahedra, corners with eight equivalent AlNb4Al8 cuboctahedra, edges with eight equivalent NbAl12 cuboctahedra, edges with sixteen equivalent AlTa2Nb2Al8 cuboctahedra, faces with four equivalent TaAl12 cuboctahedra, and faces with fourteen AlNb4Al8 cuboctahedra. There are four shorter (2.73 Å) and eight longer (2.88 Å) Ta–Al bond lengths. Nb is bonded to twelve Al atoms to form NbAl12 cuboctahedra that share corners with four equivalent NbAl12 cuboctahedra, corners with eight equivalent AlTa4Al8 cuboctahedra, edges with eight equivalent TaAl12 cuboctahedra, edges with sixteen equivalent AlTa2Nb2Al8 cuboctahedra, faces with four equivalent NbAl12 cuboctahedra, and faces with fourteen AlNb4Al8 cuboctahedra. There are four shorter (2.73 Å) and eight longer (2.89 Å) Nb–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded to four equivalent Nb and eight equivalent Al atoms to form AlNb4Al8 cuboctahedra that share corners with four equivalent AlNb4Al8 cuboctahedra, corners with eight equivalent TaAl12 cuboctahedra, edges with twenty-four AlTa4Al8 cuboctahedra, faces with two equivalent TaAl12 cuboctahedra, faces with four equivalent NbAl12 cuboctahedra, and faces with twelve AlNb4Al8 cuboctahedra. All Al–Al bond lengths are 2.89 Å. In the second Al site, Al is bonded to four equivalent Ta and eight equivalent Al atoms to form distorted AlTa4Al8 cuboctahedra that share corners with four equivalent AlTa4Al8 cuboctahedra, corners with eight equivalent NbAl12 cuboctahedra, edges with twenty-four AlNb4Al8 cuboctahedra, faces with two equivalent NbAl12 cuboctahedra, faces with four equivalent TaAl12 cuboctahedra, and faces with twelve AlTa4Al8 cuboctahedra. All Al–Al bond lengths are 2.88 Å. In the third Al site, Al is bonded to two equivalent Ta, two equivalent Nb, and eight Al atoms to form AlTa2Nb2Al8 cuboctahedra that share corners with twelve equivalent AlTa2Nb2Al8 cuboctahedra, edges with four equivalent TaAl12 cuboctahedra, edges with four equivalent NbAl12 cuboctahedra, edges with sixteen AlNb4Al8 cuboctahedra, faces with two equivalent TaAl12 cuboctahedra, faces with two equivalent NbAl12 cuboctahedra, and faces with fourteen AlNb4Al8 cuboctahedra. All Al–Al bond lengths are 2.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3LaTa2(CoO6)2 by Materials Project

Sr3LaTa2(CoO6)2 is (Cubic) Perovskite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, a faceface with one LaO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.75–2.92 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, a faceface with one LaO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.81–2.95 Å. In the third Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, a faceface with one LaO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.71–3.06 Å. In the fourth Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two SrO12 cuboctahedra, faces with four equivalent LaO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.77–2.89 Å. In the fifth Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, a faceface with one LaO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.74–3.03 Å. In the sixth Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two SrO12 cuboctahedra, faces with four equivalent LaO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.79–2.92 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of La–O bond distances ranging from 2.71–2.98 Å. In the second La3+ site, La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four CoO6 octahedra. There are a spread of La–O bond distances ranging from 2.67–3.04 Å. There are four inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share a cornercorner with one TaO6 octahedra, corners with five CoO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–9°. There are a spread of Ta–O bond distances ranging from 1.91–2.05 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two TaO6 octahedra, corners with four equivalent CoO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–10°. There are a spread of Ta–O bond distances ranging from 1.97–1.99 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share a cornercorner with one TaO6 octahedra, corners with five CoO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–6°. There are a spread of Ta–O bond distances ranging from 1.93–2.07 Å. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six CoO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–8°. There are a spread of Ta–O bond distances ranging from 1.97–2.07 Å. There are four inequivalent Co+2.50+ sites. In the first Co+2.50+ site, Co+2.50+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six TaO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–8°. There are a spread of Co–O bond distances ranging from 2.01–2.07 Å. In the second Co+2.50+ site, Co+2.50+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one CoO6 octahedra, corners with five TaO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 3–9°. There are a spread of Co–O bond distances ranging from 1.91–2.07 Å. In the third Co+2.50+ site, Co+2.50+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two CoO6 octahedra, corners with four equivalent TaO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–10°. There are a spread of Co–O bond distances ranging from 1.81–2.08 Å. In the fourth Co+2.50+ site, Co+2.50+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one CoO6 octahedra, corners with five TaO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are three shorter (2.06 Å) and three longer (2.07 Å) Co–O bond lengths. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two Co+2.50+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent La3+, one Ta5+, and one Co+2.50+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the seventh O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the eighth O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the ninth O2- site, O2- is bonded in a distorted linear geometry to four Sr2+, one Ta5+, and one Co+2.50+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the twelfth O2- site, O2- is bonded in a distorted linear geometry to four Sr2+, one Ta5+, and one Co+2.50+ atom. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the fourteenth O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two equivalent La3+, and two Co+2.50+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent La3+, and two Ta5+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the nineteenth O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the twentieth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the twenty-first O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two Ta5+ atoms. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the twenty-third O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, one Ta5+, and one Co+2.50+ atom. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two equivalent La3+, one Ta5+, and one Co+2.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li(TaS2)2 by Materials Project

Li(TaS2)2 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Li(TaS2)2 sheet oriented in the (0, 0, 1) direction. Li1+ is bonded to six equivalent S2- atoms to form LiS6 octahedra that share corners with twelve equivalent TaS6 pentagonal pyramids, edges with six equivalent LiS6 octahedra, and faces with two equivalent TaS6 pentagonal pyramids. All Li–S bond lengths are 2.56 Å. Ta+3.50+ is bonded to six S2- atoms to form distorted TaS6 pentagonal pyramids that share corners with six equivalent LiS6 octahedra, edges with six equivalent TaS6 pentagonal pyramids, and a faceface with one LiS6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are three shorter (2.47 Å) and three longer (2.51 Å) Ta–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent Li1+ and three equivalent Ta+3.50+ atoms to form a mixture of distorted corner and edge-sharing SLi3Ta3 pentagonal pyramids. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Ta+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta5CrNiS10 by Materials Project

Ta2CrS4Ta2NiS4TaS2 crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of two Ta2CrS4 sheets oriented in the (0, 0, 1) direction; two Ta2NiS4 sheets oriented in the (0, 0, 1) direction; and two TaS2 sheets oriented in the (0, 0, 1) direction. In each Ta2CrS4 sheet, Ta3+ is bonded to six S2- atoms to form distorted TaS6 pentagonal pyramids that share corners with six equivalent CrS6 octahedra, edges with six equivalent TaS6 pentagonal pyramids, and a faceface with one CrS6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are three shorter (2.48 Å) and three longer (2.52 Å) Ta–S bond lengths. Cr3+ is bonded to six equivalent S2- atoms to form CrS6 octahedra that share corners with twelve equivalent TaS6 pentagonal pyramids, edges with six equivalent CrS6 octahedra, and faces with two equivalent TaS6 pentagonal pyramids. All Cr–S bond lengths are 2.43 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent Ta3+ and three equivalent Cr3+ atoms to form a mixture of distorted corner and edge-sharing STa3Cr3 pentagonal pyramids. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta3+ atoms. In each Ta2NiS4 sheet, there are two inequivalent Ta3+ sites. In the first Ta3+ site, Ta3+ is bonded to six S2- atoms to form distorted TaS6 pentagonal pyramids that share corners with six equivalent NiS6 octahedra, edges with six equivalent TaS6 pentagonal pyramids, and a faceface with one NiS6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Ta–S bond lengths are 2.48 Å. In the second Ta3+ site, Ta3+ is bonded to six S2- atoms to form distorted TaS6 pentagonal pyramids that share corners with six equivalent NiS6 octahedra, edges with six equivalent TaS6 pentagonal pyramids, and a faceface with one NiS6 octahedra. The corner-sharing octahedral tilt angles are 47°. All Ta–S bond lengths are 2.48 Å. Ni2+ is bonded to six S2- atoms to form NiS6 octahedra that share corners with twelve TaS6 pentagonal pyramids, edges with six equivalent NiS6 octahedra, and faces with two TaS6 pentagonal pyramids. All Ni–S bond lengths are 2.38 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta3+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta3+ atoms. In the third S2- site, S2- is bonded to three equivalent Ta3+ and three equivalent Ni2+ atoms to form a mixture of distorted corner and edge-sharing STa3Ni3 pentagonal pyramids. In the fourth S2- site, S2- is bonded to three equivalent Ta3+ and three equivalent Ni2+ atoms to form a mixture of distorted corner and edge-sharing STa3Ni3 pentagonal pyramids. In each TaS2 sheet, Ta3+ is bonded to six equivalent S2- atoms to form distorted edge-sharing TaS6 pentagonal pyramids. All Ta–S bond lengths are 2.48 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Ta3+ atoms.

36 MATERIALS SCIENCE↗