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HfS is Tungsten Carbide structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Hf is bonded to six equivalent S atoms to form a mixture of distorted corner, edge, and face-sharing HfS6 pentagonal pyramids. All Hf–S bond lengths are 2.61 Å. S is bonded to six equivalent Hf atoms to form a mixture of distorted corner, edge, and face-sharing SHf6 pentagonal pyramids.
La3Hf is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. La is bonded to eight equivalent La and four equivalent Hf atoms to form distorted LaLa8Hf4 cuboctahedra that share corners with four equivalent HfLa12 cuboctahedra, corners with fourteen equivalent LaLa8Hf4 cuboctahedra, edges with six equivalent HfLa12 cuboctahedra, edges with twelve equivalent LaLa8Hf4 cuboctahedra, faces with four equivalent HfLa12 cuboctahedra, and faces with sixteen equivalent LaLa8Hf4 cuboctahedra. There are a spread of La–La bond distances ranging from 3.44–3.75 Å. There are two shorter (3.53 Å) and two longer (3.59 Å) La–Hf bond lengths. Hf is bonded to twelve equivalent La atoms to form HfLa12 cuboctahedra that share corners with six equivalent HfLa12 cuboctahedra, corners with twelve equivalent LaLa8Hf4 cuboctahedra, edges with eighteen equivalent LaLa8Hf4 cuboctahedra, faces with eight equivalent HfLa12 cuboctahedra, and faces with twelve equivalent LaLa8Hf4 cuboctahedra.
HfAu2Sn crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two HfAu2Sn ribbons oriented in the (1, 0, 0) direction. Hf is bonded in a linear geometry to two equivalent Au atoms. Both Hf–Au bond lengths are 2.59 Å. Au is bonded in a linear geometry to one Hf and one Sn atom. The Au–Sn bond length is 2.70 Å. Sn is bonded in a linear geometry to two equivalent Au atoms.
ScHfZn2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two ScHfZn2 ribbons oriented in the (1, 0, 0) direction. Sc is bonded in a linear geometry to two equivalent Zn atoms. Both Sc–Zn bond lengths are 2.88 Å. Hf is bonded in a linear geometry to two equivalent Zn atoms. Both Hf–Zn bond lengths are 2.79 Å. Zn is bonded in a linear geometry to one Sc and one Hf atom.
Pd2HfGa crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two Pd2HfGa ribbons oriented in the (1, 0, 0) direction. Hf is bonded in a linear geometry to two equivalent Pd atoms. Both Hf–Pd bond lengths are 2.33 Å. Pd is bonded in a linear geometry to one Hf and one Ga atom. The Pd–Ga bond length is 2.51 Å. Ga is bonded in a linear geometry to two equivalent Pd atoms.
ScHfHg2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two ScHfHg2 ribbons oriented in the (1, 0, 0) direction. Sc is bonded in a linear geometry to two equivalent Hg atoms. Both Sc–Hg bond lengths are 2.93 Å. Hf is bonded in a linear geometry to two equivalent Hg atoms. Both Hf–Hg bond lengths are 2.90 Å. Hg is bonded in a linear geometry to one Sc and one Hf atom.
HfO2(Ge) crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Hf is bonded to six equivalent O atoms to form distorted edge-sharing HfO6 octahedra. There are a spread of Hf–O bond distances ranging from 2.14–2.26 Å. Ge is bonded in a distorted square co-planar geometry to four equivalent O atoms. There are two shorter (2.48 Å) and two longer (2.58 Å) Ge–O bond lengths. O is bonded in a 5-coordinate geometry to three equivalent Hf and two equivalent Ge atoms.
Hf2(TiGa)3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. Hf is bonded in a 6-coordinate geometry to six equivalent Ga atoms. All Hf–Ga bond lengths are 2.79 Å. Ti is bonded in a 5-coordinate geometry to five equivalent Ga atoms. There are a spread of Ti–Ga bond distances ranging from 2.62–3.04 Å. Ga is bonded in a 9-coordinate geometry to four equivalent Hf and five equivalent Ti atoms.
Hf3Ti2(PbO3)5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with three HfO6 octahedra and corners with three TiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–14°. There are a spread of Hf–O bond distances ranging from 2.01–2.21 Å. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with two TiO6 octahedra and corners with four HfO6 octahedra. The corner-sharing octahedra tilt angles range from 10–14°. There are a spread of Hf–O bond distances ranging from 2.02–2.23 Å. In the third Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with three HfO6 octahedra and corners with three TiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–15°. There are a spread of Hf–O bond distances ranging from 2.04–2.14 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra and corners with four HfO6 octahedra. The corner-sharing octahedra tilt angles range from 10–14°. There are a spread of Ti–O bond distances ranging from 1.89–2.14 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra and corners with four HfO6 octahedra. The corner-sharing octahedra tilt angles range from 12–15°. There are a spread of Ti–O bond distances ranging from 1.87–2.26 Å. There are five inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 12-coordinate geometry to nine O2- atoms. There are a spread of Pb–O bond distances ranging from 2.53–2.97 Å. In the second Pb2+ site, Pb2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pb–O bond distances ranging from 2.52–2.95 Å. In the third Pb2+ site, Pb2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pb–O bond distances ranging from 2.44–3.01 Å. In the fourth Pb2+ site, Pb2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pb–O bond distances ranging from 2.46–3.03 Å. In the fifth Pb2+ site, Pb2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.47–3.23 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Hf4+, one Ti4+, and three Pb2+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Hf4+, one Ti4+, and three Pb2+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Hf4+, one Ti4+, and three Pb2+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Hf4+, one Ti4+, and three Pb2+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Hf4+ and three Pb2+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Hf4+, one Ti4+, and four Pb2+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Ti4+ and three Pb2+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Hf4+, one Ti4+, and three Pb2+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Hf4+ and three Pb2+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Hf4+ and three Pb2+ atoms.
HfBO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Hf is bonded to twelve equivalent O atoms to form HfO12 cuboctahedra that share corners with twelve equivalent HfO12 cuboctahedra, faces with six equivalent HfO12 cuboctahedra, and faces with eight equivalent BO6 octahedra. All Hf–O bond lengths are 2.42 Å. B is bonded to six equivalent O atoms to form BO6 octahedra that share corners with six equivalent BO6 octahedra and faces with eight equivalent HfO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All B–O bond lengths are 1.71 Å. O is bonded to four equivalent Hf and two equivalent B atoms to form a mixture of distorted face, edge, and corner-sharing OHf4B2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°.
HfNb crystallizes in the orthorhombic Cmmm space group. The structure is two-dimensional and consists of two HfNb sheets oriented in the (0, 1, 0) direction. Hf is bonded in a 12-coordinate geometry to four equivalent Nb atoms. All Hf–Nb bond lengths are 2.96 Å. Nb is bonded in a 12-coordinate geometry to four equivalent Hf atoms.
HfZrRu2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two HfZrRu2 ribbons oriented in the (1, 0, 0) direction. Hf is bonded in a linear geometry to two equivalent Ru atoms. Both Hf–Ru bond lengths are 2.30 Å. Zr is bonded in a linear geometry to two equivalent Ru atoms. Both Zr–Ru bond lengths are 2.28 Å. Ru is bonded in a linear geometry to one Hf and one Zr atom.
LiHfHg2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two LiHfHg2 ribbons oriented in the (1, 0, 0) direction. Li is bonded in a linear geometry to two equivalent Hg atoms. Both Li–Hg bond lengths are 2.74 Å. Hf is bonded in a linear geometry to two equivalent Hg atoms. Both Hf–Hg bond lengths are 2.96 Å. Hg is bonded in a linear geometry to one Li and one Hf atom.
HfTaMo2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two HfTaMo2 ribbons oriented in the (1, 0, 0) direction. Hf is bonded in a linear geometry to two equivalent Mo atoms. Both Hf–Mo bond lengths are 2.41 Å. Ta is bonded in a linear geometry to two equivalent Mo atoms. Both Ta–Mo bond lengths are 2.31 Å. Mo is bonded in a linear geometry to one Hf and one Ta atom.
MgHfCu2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two MgHfCu2 ribbons oriented in the (0, 1, 0) direction. Mg is bonded in a linear geometry to two equivalent Cu atoms. Both Mg–Cu bond lengths are 2.60 Å. Hf is bonded in a linear geometry to two equivalent Cu atoms. Both Hf–Cu bond lengths are 2.57 Å. Cu is bonded in a linear geometry to one Mg and one Hf atom.
HfTiZn2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to eight equivalent Zn atoms. All Hf–Zn bond lengths are 2.80 Å. Ti is bonded in a distorted body-centered cubic geometry to eight equivalent Zn atoms. All Ti–Zn bond lengths are 2.80 Å. Zn is bonded in a body-centered cubic geometry to four equivalent Hf and four equivalent Ti atoms.
CaHfRh2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two CaHfRh2 ribbons oriented in the (1, 0, 0) direction. Ca is bonded in a linear geometry to two equivalent Rh atoms. Both Ca–Rh bond lengths are 2.73 Å. Hf is bonded in a linear geometry to two equivalent Rh atoms. Both Hf–Rh bond lengths are 2.23 Å. Rh is bonded in a linear geometry to one Ca and one Hf atom.
Hf2Ge crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. Hf is bonded in a 2-coordinate geometry to two equivalent Ge atoms. Both Hf–Ge bond lengths are 2.68 Å. Ge is bonded to four equivalent Hf and two equivalent Ge atoms to form distorted corner-sharing GeHf4Ge2 octahedra. The corner-sharing octahedra tilt angles range from 0–44°. Both Ge–Ge bond lengths are 2.57 Å.