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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on HfAl2 by Materials Project

HfAl2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to four equivalent Hf and twelve Al atoms. There are three shorter (3.23 Å) and one longer (3.25 Å) Hf–Hf bond lengths. There are a spread of Hf–Al bond distances ranging from 3.08–3.11 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six equivalent Hf and six equivalent Al atoms to form a mixture of edge, face, and corner-sharing AlHf6Al6 cuboctahedra. All Al–Al bond lengths are 2.68 Å. In the second Al site, Al is bonded to six equivalent Hf and six Al atoms to form a mixture of edge, face, and corner-sharing AlHf6Al6 cuboctahedra. There are two shorter (2.56 Å) and two longer (2.69 Å) Al–Al bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf2Al by Materials Project

Hf2Al is Khatyrkite structured and crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. Hf is bonded in a 4-coordinate geometry to one Hf and four equivalent Al atoms. The Hf–Hf bond length is 2.93 Å. All Hf–Al bond lengths are 2.91 Å. Al is bonded in a 10-coordinate geometry to eight equivalent Hf and two equivalent Al atoms. Both Al–Al bond lengths are 2.61 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5Al3 by Materials Project

Hf5Al3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 5-coordinate geometry to five equivalent Al atoms. There are a spread of Hf–Al bond distances ranging from 2.81–3.13 Å. In the second Hf site, Hf is bonded in a 6-coordinate geometry to two equivalent Hf and six equivalent Al atoms. Both Hf–Hf bond lengths are 2.85 Å. All Hf–Al bond lengths are 2.87 Å. Al is bonded in a 9-coordinate geometry to nine Hf atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfAl by Materials Project

HfAl crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Hf is bonded in a 7-coordinate geometry to seven equivalent Al atoms. There are a spread of Hf–Al bond distances ranging from 2.88–3.02 Å. Al is bonded in a 9-coordinate geometry to seven equivalent Hf and two equivalent Al atoms. Both Al–Al bond lengths are 2.64 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfAl3 by Materials Project

Al3Hf is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Hf is bonded to twelve Al atoms to form HfAl12 cuboctahedra that share corners with four equivalent HfAl12 cuboctahedra, edges with eight equivalent HfAl12 cuboctahedra, edges with sixteen equivalent AlHf4Al8 cuboctahedra, faces with four equivalent HfAl12 cuboctahedra, and faces with eight equivalent AlHf4Al8 cuboctahedra. There are four shorter (2.79 Å) and eight longer (2.98 Å) Hf–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a distorted square co-planar geometry to four equivalent Hf and eight equivalent Al atoms. All Al–Al bond lengths are 2.98 Å. In the second Al site, Al is bonded to four equivalent Hf and eight Al atoms to form AlHf4Al8 cuboctahedra that share corners with twelve equivalent AlHf4Al8 cuboctahedra, edges with eight equivalent HfAl12 cuboctahedra, edges with eight equivalent AlHf4Al8 cuboctahedra, faces with four equivalent HfAl12 cuboctahedra, and faces with ten equivalent AlHf4Al8 cuboctahedra. All Al–Al bond lengths are 2.79 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfAl3 by Materials Project

Al3Hf is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Hf is bonded to twelve Al atoms to form HfAl12 cuboctahedra that share corners with four equivalent AlHf4Al8 cuboctahedra, corners with eight equivalent HfAl12 cuboctahedra, edges with four equivalent HfAl12 cuboctahedra, edges with twenty AlHf4Al8 cuboctahedra, faces with five equivalent HfAl12 cuboctahedra, and faces with thirteen AlHf4Al8 cuboctahedra. There are a spread of Hf–Al bond distances ranging from 2.83–3.00 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded to four equivalent Hf and eight Al atoms to form distorted AlHf4Al8 cuboctahedra that share corners with four equivalent HfAl12 cuboctahedra, corners with eight equivalent AlHf4Al8 cuboctahedra, edges with four equivalent HfAl12 cuboctahedra, edges with twenty AlHf4Al8 cuboctahedra, faces with five equivalent HfAl12 cuboctahedra, and faces with thirteen AlHf4Al8 cuboctahedra. There are four shorter (2.93 Å) and four longer (2.94 Å) Al–Al bond lengths. In the second Al site, Al is bonded to four equivalent Hf and eight Al atoms to form distorted AlHf4Al8 cuboctahedra that share corners with twelve AlHf4Al8 cuboctahedra, edges with eight equivalent HfAl12 cuboctahedra, edges with sixteen AlHf4Al8 cuboctahedra, faces with four equivalent HfAl12 cuboctahedra, and faces with fourteen AlHf4Al8 cuboctahedra. All Al–Al bond lengths are 2.83 Å. In the third Al site, Al is bonded to four equivalent Hf and eight Al atoms to form AlHf4Al8 cuboctahedra that share corners with twelve AlHf4Al8 cuboctahedra, edges with eight equivalent HfAl12 cuboctahedra, edges with sixteen AlHf4Al8 cuboctahedra, faces with four equivalent HfAl12 cuboctahedra, and faces with fourteen AlHf4Al8 cuboctahedra. All Al–Al bond lengths are 2.83 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf2Al3 by Materials Project

Hf2Al3 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. Hf is bonded in a 7-coordinate geometry to nine Al atoms. There are a spread of Hf–Al bond distances ranging from 2.84–3.17 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to six equivalent Hf and four equivalent Al atoms. There are two shorter (2.66 Å) and two longer (2.70 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 10-coordinate geometry to six equivalent Hf and four Al atoms. Both Al–Al bond lengths are 2.77 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3Al2 by Materials Project

Hf3Al2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 6-coordinate geometry to six equivalent Al atoms. There are two shorter (2.80 Å) and four longer (2.91 Å) Hf–Al bond lengths. In the second Hf site, Hf is bonded in a distorted square co-planar geometry to four equivalent Al atoms. All Hf–Al bond lengths are 3.03 Å. In the third Hf site, Hf is bonded in a 6-coordinate geometry to six equivalent Al atoms. There are two shorter (2.75 Å) and four longer (2.91 Å) Hf–Al bond lengths. Al is bonded in a 10-coordinate geometry to eight Hf and two equivalent Al atoms. There are one shorter (2.60 Å) and one longer (2.89 Å) Al–Al bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfAl3 by Materials Project

Al3Hf is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Hf is bonded to twelve equivalent Al atoms to form HfAl12 cuboctahedra that share corners with twelve equivalent HfAl12 cuboctahedra, edges with twenty-four equivalent AlHf4Al8 cuboctahedra, faces with six equivalent HfAl12 cuboctahedra, and faces with twelve equivalent AlHf4Al8 cuboctahedra. All Hf–Al bond lengths are 2.89 Å. Al is bonded to four equivalent Hf and eight equivalent Al atoms to form AlHf4Al8 cuboctahedra that share corners with twelve equivalent AlHf4Al8 cuboctahedra, edges with eight equivalent HfAl12 cuboctahedra, edges with sixteen equivalent AlHf4Al8 cuboctahedra, faces with four equivalent HfAl12 cuboctahedra, and faces with fourteen equivalent AlHf4Al8 cuboctahedra. All Al–Al bond lengths are 2.89 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3Al by Materials Project

Hf3Al is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded to eight equivalent Hf and four equivalent Al atoms to form distorted HfHf8Al4 cuboctahedra that share corners with four equivalent AlHf12 cuboctahedra, corners with fourteen equivalent HfHf8Al4 cuboctahedra, edges with six equivalent AlHf12 cuboctahedra, edges with twelve equivalent HfHf8Al4 cuboctahedra, faces with four equivalent AlHf12 cuboctahedra, and faces with sixteen equivalent HfHf8Al4 cuboctahedra. There are a spread of Hf–Hf bond distances ranging from 3.02–3.13 Å. There are two shorter (3.05 Å) and two longer (3.08 Å) Hf–Al bond lengths. Al is bonded to twelve equivalent Hf atoms to form AlHf12 cuboctahedra that share corners with six equivalent AlHf12 cuboctahedra, corners with twelve equivalent HfHf8Al4 cuboctahedra, edges with eighteen equivalent HfHf8Al4 cuboctahedra, faces with eight equivalent AlHf12 cuboctahedra, and faces with twelve equivalent HfHf8Al4 cuboctahedra.

36 MATERIALS SCIENCE↗