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DOE OSTI2020

Materials Data on HfBrN by Materials Project

HfNBr crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three HfNBr sheets oriented in the (0, 0, 1) direction. Hf4+ is bonded in a 4-coordinate geometry to four equivalent N3- and three equivalent Br1- atoms. There are three shorter (2.14 Å) and one longer (2.16 Å) Hf–N bond lengths. All Hf–Br bond lengths are 2.89 Å. N3- is bonded to four equivalent Hf4+ atoms to form a mixture of corner and edge-sharing NHf4 tetrahedra. Br1- is bonded in a 3-coordinate geometry to three equivalent Hf4+ atoms.

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Materials Data on HfF4 by Materials Project

HfF4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Hf–F bond distances ranging from 2.08–2.19 Å. In the second Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Hf–F bond distances ranging from 2.06–2.15 Å. There are seven inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Hf4+ atoms. In the second F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two Hf4+ atoms. In the third F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Hf4+ atoms. In the fourth F1- site, F1- is bonded in a distorted linear geometry to two Hf4+ atoms. In the fifth F1- site, F1- is bonded in a bent 150 degrees geometry to two Hf4+ atoms. In the sixth F1- site, F1- is bonded in a linear geometry to two equivalent Hf4+ atoms. In the seventh F1- site, F1- is bonded in a bent 150 degrees geometry to two Hf4+ atoms.

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Materials Data on Hf2Bi2O7 by Materials Project

Hf2Bi2O7 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedra tilt angles range from 37–52°. There are a spread of Hf–O bond distances ranging from 2.02–2.17 Å. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedra tilt angles range from 39–51°. There are a spread of Hf–O bond distances ranging from 2.05–2.13 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.23–3.05 Å. In the second Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.24–2.86 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Hf4+ and two equivalent Bi3+ atoms. In the second O2- site, O2- is bonded to four Bi3+ atoms to form corner-sharing OBi4 tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Hf4+ and one Bi3+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Hf4+ and one Bi3+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Hf4+ and two Bi3+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Hf4+ and one Bi3+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Hf4+ and two equivalent Bi3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Hf4+ and two equivalent Bi3+ atoms. In the ninth O2- site, O2- is bonded to four Bi3+ atoms to form corner-sharing OBi4 tetrahedra. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Hf4+ and two equivalent Bi3+ atoms.

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Materials Data on HfNCl by Materials Project

HfNCl crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three HfNCl sheets oriented in the (0, 0, 1) direction. Hf4+ is bonded in a 7-coordinate geometry to four equivalent N3- and three equivalent Cl1- atoms. There are three shorter (2.11 Å) and one longer (2.18 Å) Hf–N bond lengths. All Hf–Cl bond lengths are 2.75 Å. N3- is bonded to four equivalent Hf4+ atoms to form a mixture of edge and corner-sharing NHf4 tetrahedra. Cl1- is bonded in a 3-coordinate geometry to three equivalent Hf4+ atoms.

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Materials Data on Rb4Hf3S14 by Materials Project

Rb4Hf3S14 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 10-coordinate geometry to ten S+1.14- atoms. There are a spread of Rb–S bond distances ranging from 3.33–3.87 Å. In the second Rb1+ site, Rb1+ is bonded in a 10-coordinate geometry to ten S+1.14- atoms. There are a spread of Rb–S bond distances ranging from 3.39–4.02 Å. There are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to seven S+1.14- atoms to form distorted HfS7 pentagonal bipyramids that share an edgeedge with one HfS7 pentagonal bipyramid and a faceface with one HfS8 hexagonal bipyramid. There are a spread of Hf–S bond distances ranging from 2.44–2.77 Å. In the second Hf4+ site, Hf4+ is bonded to eight S+1.14- atoms to form distorted face-sharing HfS8 hexagonal bipyramids. There are a spread of Hf–S bond distances ranging from 2.56–2.69 Å. There are seven inequivalent S+1.14- sites. In the first S+1.14- site, S+1.14- is bonded in a 5-coordinate geometry to two equivalent Rb1+, two Hf4+, and one S+1.14- atom. The S–S bond length is 2.10 Å. In the second S+1.14- site, S+1.14- is bonded in a 2-coordinate geometry to three Rb1+ and two Hf4+ atoms. In the third S+1.14- site, S+1.14- is bonded in a 2-coordinate geometry to two Rb1+, two Hf4+, and one S+1.14- atom. The S–S bond length is 2.11 Å. In the fourth S+1.14- site, S+1.14- is bonded in a 2-coordinate geometry to three Rb1+ and two equivalent Hf4+ atoms. In the fifth S+1.14- site, S+1.14- is bonded in a 1-coordinate geometry to four Rb1+ and one Hf4+ atom. In the sixth S+1.14- site, S+1.14- is bonded in a 1-coordinate geometry to three Rb1+, one Hf4+, and one S+1.14- atom. In the seventh S+1.14- site, S+1.14- is bonded in a 1-coordinate geometry to three Rb1+, one Hf4+, and one S+1.14- atom.

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Materials Data on Hf2P2O9 by Materials Project

Hf2P2O9 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to seven O2- atoms to form HfO7 pentagonal bipyramids that share a cornercorner with one HfO6 octahedra, corners with four PO4 tetrahedra, an edgeedge with one HfO6 octahedra, an edgeedge with one HfO7 pentagonal bipyramid, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. There are a spread of Hf–O bond distances ranging from 2.05–2.33 Å. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share a cornercorner with one HfO7 pentagonal bipyramid, corners with four PO4 tetrahedra, an edgeedge with one HfO6 octahedra, and an edgeedge with one HfO7 pentagonal bipyramid. There are a spread of Hf–O bond distances ranging from 2.01–2.15 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent HfO6 octahedra, a cornercorner with one HfO7 pentagonal bipyramid, and an edgeedge with one HfO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 23–28°. There is two shorter (1.52 Å) and two longer (1.57 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one HfO6 octahedra and corners with three equivalent HfO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Hf4+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Hf4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Hf4+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom.

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Materials Data on HfSCl6O by Materials Project

HfSOCl6 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two HfSOCl6 clusters. Hf4+ is bonded to one O2- and five Cl1- atoms to form edge-sharing HfCl5O octahedra. The Hf–O bond length is 2.30 Å. There are a spread of Hf–Cl bond distances ranging from 2.34–2.60 Å. S4+ is bonded in a trigonal non-coplanar geometry to one O2- and two Cl1- atoms. The S–O bond length is 1.48 Å. There are one shorter (2.06 Å) and one longer (2.07 Å) S–Cl bond lengths. O2- is bonded in a distorted bent 150 degrees geometry to one Hf4+ and one S4+ atom. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Hf4+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Hf4+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Hf4+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one S4+ atom. In the fifth Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent Hf4+ atoms. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one S4+ atom.

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Materials Data on Ba4Hf3O10 by Materials Project

Ba4Hf3O10 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eight equivalent BaO12 cuboctahedra, faces with five equivalent BaO12 cuboctahedra, and faces with eight HfO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.85–3.09 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–2.98 Å. There are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six HfO6 octahedra and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are two shorter (2.10 Å) and four longer (2.11 Å) Hf–O bond lengths. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with five HfO6 octahedra and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Hf–O bond distances ranging from 2.09–2.13 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent Ba2+ and two equivalent Hf4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Hf4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Hf4+ atoms. In the fourth O2- site, O2- is bonded to five equivalent Ba2+ and one Hf4+ atom to form a mixture of distorted corner and edge-sharing OBa5Hf octahedra. The corner-sharing octahedral tilt angles are 5°.

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Materials Data on HfIN by Materials Project

HfNI crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three HfNI sheets oriented in the (0, 0, 1) direction. Hf4+ is bonded in a 4-coordinate geometry to four equivalent N3- and three equivalent I1- atoms. There are one shorter (2.13 Å) and three longer (2.18 Å) Hf–N bond lengths. All Hf–I bond lengths are 3.07 Å. N3- is bonded to four equivalent Hf4+ atoms to form a mixture of distorted corner and edge-sharing NHf4 trigonal pyramids. I1- is bonded in a 12-coordinate geometry to three equivalent Hf4+ atoms.

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Materials Data on Hf3(Al2C3)2 by Materials Project

Hf3Al4C6 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six C4- atoms to form HfC6 octahedra that share corners with three equivalent HfC6 octahedra, corners with three equivalent AlC4 tetrahedra, edges with nine HfC6 octahedra, and edges with three equivalent AlC4 tetrahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.33 Å) and three longer (2.37 Å) Hf–C bond lengths. In the second Hf4+ site, Hf4+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing HfC6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Hf–C bond lengths are 2.34 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four C4- atoms to form AlC4 tetrahedra that share corners with three equivalent HfC6 octahedra, corners with six equivalent AlC4 tetrahedra, corners with four equivalent AlC4 trigonal pyramids, and edges with three equivalent HfC6 octahedra. The corner-sharing octahedral tilt angles are 10°. There are one shorter (1.95 Å) and three longer (2.13 Å) Al–C bond lengths. In the second Al3+ site, Al3+ is bonded to four equivalent C4- atoms to form a mixture of distorted corner and edge-sharing AlC4 trigonal pyramids. There are three shorter (1.95 Å) and one longer (2.19 Å) Al–C bond lengths. There are three inequivalent C4- sites. In the first C4- site, C4- is bonded to six Hf4+ atoms to form a mixture of corner and edge-sharing CHf6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second C4- site, C4- is bonded to five Al3+ atoms to form CAl5 trigonal bipyramids that share corners with three equivalent CHf3Al3 octahedra, corners with six equivalent CAl5 trigonal bipyramids, and edges with three equivalent CAl5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. In the third C4- site, C4- is bonded to three equivalent Hf4+ and three equivalent Al3+ atoms to form CHf3Al3 octahedra that share corners with three equivalent CHf6 octahedra, corners with three equivalent CAl5 trigonal bipyramids, and edges with nine CHf6 octahedra. The corner-sharing octahedral tilt angles are 1°.

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Materials Data on HfBrN by Materials Project

HfNBr crystallizes in the orthorhombic Pmmn space group. The structure is two-dimensional and consists of one HfNBr sheet oriented in the (0, 0, 1) direction. Hf4+ is bonded in a 6-coordinate geometry to four equivalent N3- and two equivalent Br1- atoms. There are two shorter (2.13 Å) and two longer (2.14 Å) Hf–N bond lengths. Both Hf–Br bond lengths are 2.75 Å. N3- is bonded to four equivalent Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 tetrahedra. Br1- is bonded in an L-shaped geometry to two equivalent Hf4+ atoms.

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Materials Data on Hf3Tl2(CuSe4)2 by Materials Project

Tl2Cu2Hf3Se8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six Se2- atoms to form HfSe6 octahedra that share a cornercorner with one HfSe6 octahedra, edges with four equivalent HfSe6 octahedra, and edges with two equivalent CuSe4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Hf–Se bond distances ranging from 2.68–2.72 Å. In the second Hf4+ site, Hf4+ is bonded to six Se2- atoms to form HfSe6 octahedra that share corners with two equivalent HfSe6 octahedra, edges with two equivalent HfSe6 octahedra, and edges with four equivalent CuSe4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are two shorter (2.70 Å) and four longer (2.71 Å) Hf–Se bond lengths. Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with two equivalent CuSe4 tetrahedra and edges with four HfSe6 octahedra. There are two shorter (2.43 Å) and two longer (2.48 Å) Cu–Se bond lengths. Tl1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.36–3.67 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Hf4+, one Cu1+, and three equivalent Tl1+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Hf4+, one Cu1+, and two equivalent Tl1+ atoms. In the third Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Hf4+ and one Tl1+ atom. In the fourth Se2- site, Se2- is bonded in a 6-coordinate geometry to two Hf4+, two equivalent Cu1+, and two equivalent Tl1+ atoms.

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Materials Data on Hf5Sb9 by Materials Project

Hf5Sb9 crystallizes in the tetragonal P4/n space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded in a 9-coordinate geometry to nine Sb+2.22- atoms. There are a spread of Hf–Sb bond distances ranging from 3.03–3.09 Å. In the second Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight Sb+2.22- atoms. There are a spread of Hf–Sb bond distances ranging from 2.91–3.21 Å. There are three inequivalent Sb+2.22- sites. In the first Sb+2.22- site, Sb+2.22- is bonded in a 4-coordinate geometry to four Hf4+ atoms. In the second Sb+2.22- site, Sb+2.22- is bonded in a 5-coordinate geometry to five Hf4+ atoms. In the third Sb+2.22- site, Sb+2.22- is bonded in a 5-coordinate geometry to five Hf4+ atoms.

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Materials Data on HfPbO3 by Materials Project

PbHfO3 crystallizes in the orthorhombic Pba2 space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedra tilt angles range from 2–19°. There are a spread of Hf–O bond distances ranging from 2.03–2.22 Å. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedra tilt angles range from 8–19°. There are a spread of Hf–O bond distances ranging from 2.04–2.22 Å. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 12-coordinate geometry to seven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.53–3.00 Å. In the second Pb2+ site, Pb2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Pb–O bond distances ranging from 2.40–2.63 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Hf4+ and two equivalent Pb2+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Hf4+ and two equivalent Pb2+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Hf4+ and one Pb2+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Hf4+ and two Pb2+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Hf4+ and two equivalent Pb2+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Hf4+ and two Pb2+ atoms. In the seventh O2- site, O2- is bonded in a linear geometry to two equivalent Hf4+ and two equivalent Pb2+ atoms. In the eighth O2- site, O2- is bonded in a linear geometry to two equivalent Hf4+ atoms.

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Materials Data on Hf3Tl10Mo12PbO48 by Materials Project

Hf3Mo12Tl10PbO48 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six equivalent O2- atoms to form HfO6 octahedra that share corners with six equivalent MoO4 tetrahedra. All Hf–O bond lengths are 2.09 Å. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six MoO4 tetrahedra. There are three shorter (2.07 Å) and three longer (2.10 Å) Hf–O bond lengths. There are two inequivalent Mo6+ sites. In the first Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with two HfO6 octahedra. The corner-sharing octahedra tilt angles range from 35–36°. There are a spread of Mo–O bond distances ranging from 1.75–1.85 Å. In the second Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share a cornercorner with one HfO6 octahedra and a cornercorner with one PbO6 octahedra. The corner-sharing octahedra tilt angles range from 34–50°. There are a spread of Mo–O bond distances ranging from 1.77–1.87 Å. There are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Tl–O bond distances ranging from 2.84–3.37 Å. In the second Tl1+ site, Tl1+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are three shorter (2.82 Å) and three longer (3.06 Å) Tl–O bond lengths. In the third Tl1+ site, Tl1+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of Tl–O bond distances ranging from 2.85–3.52 Å. Pb2+ is bonded to six equivalent O2- atoms to form PbO6 octahedra that share corners with six equivalent MoO4 tetrahedra. All Pb–O bond lengths are 2.50 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Mo6+ and two Tl1+ atoms. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+, one Mo6+, and two Tl1+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+, one Mo6+, and one Tl1+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Hf4+, one Mo6+, and one Tl1+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Mo6+ and two Tl1+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Mo6+ and two Tl1+ atoms. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one Mo6+ and three Tl1+ atoms. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to one Mo6+, two equivalent Tl1+, and one Pb2+ atom.

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Materials Data on Hf3N4 by Materials Project

Hf3N4 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Hf–N bond distances ranging from 2.04–2.59 Å. In the second Hf4+ site, Hf4+ is bonded to six equivalent N3- atoms to form edge-sharing HfN6 octahedra. All Hf–N bond lengths are 2.27 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to six Hf4+ atoms to form distorted NHf6 octahedra that share corners with three equivalent NHf6 octahedra, corners with six equivalent NHf4 tetrahedra, edges with nine equivalent NHf6 octahedra, and edges with three equivalent NHf4 tetrahedra. The corner-sharing octahedral tilt angles are 0°. In the second N3- site, N3- is bonded to four equivalent Hf4+ atoms to form NHf4 tetrahedra that share corners with six equivalent NHf6 octahedra, corners with six equivalent NHf4 tetrahedra, edges with three equivalent NHf6 octahedra, and edges with three equivalent NHf4 tetrahedra. The corner-sharing octahedra tilt angles range from 25–50°.

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DOE OSTI2020

Materials Data on HfP2O7 by Materials Project

HfP2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six PO4 tetrahedra. There are four shorter (2.07 Å) and two longer (2.08 Å) Hf–O bond lengths. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Hf–O bond distances ranging from 2.06–2.08 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three HfO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–46°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three HfO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–48°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Hf4+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Hf4+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Hf4+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3N4 by Materials Project

Hf3N4 is Hausmannite structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six equivalent N3- atoms to form HfN6 octahedra that share corners with six equivalent HfN4 tetrahedra and edges with six equivalent HfN6 octahedra. All Hf–N bond lengths are 2.20 Å. In the second Hf4+ site, Hf4+ is bonded to four equivalent N3- atoms to form corner-sharing HfN4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. All Hf–N bond lengths are 2.09 Å. N3- is bonded in a distorted rectangular see-saw-like geometry to four Hf4+ atoms.

36 MATERIALS SCIENCE↗