DOE OSTI2020
Th8Al4H11 crystallizes in the tetragonal P-42m space group. The structure is three-dimensional. there are six inequivalent Th sites. In the first Th site, Th is bonded in a 5-coordinate geometry to four Al and five H atoms. There are two shorter (3.27 Å) and two longer (3.29 Å) Th–Al bond lengths. There are a spread of Th–H bond distances ranging from 2.28–2.43 Å. In the second Th site, Th is bonded in a 5-coordinate geometry to four Al and five H atoms. There are two shorter (3.26 Å) and two longer (3.31 Å) Th–Al bond lengths. There are a spread of Th–H bond distances ranging from 2.27–2.43 Å. In the third Th site, Th is bonded in a 7-coordinate geometry to four Al and seven H atoms. There are two shorter (3.30 Å) and two longer (3.31 Å) Th–Al bond lengths. There are a spread of Th–H bond distances ranging from 2.28–2.46 Å. In the fourth Th site, Th is bonded in a 7-coordinate geometry to four Al and seven H atoms. There are two shorter (3.29 Å) and two longer (3.30 Å) Th–Al bond lengths. There are a spread of Th–H bond distances ranging from 2.27–2.44 Å. In the fifth Th site, Th is bonded in a 5-coordinate geometry to four Al and five H atoms. All Th–Al bond lengths are 3.28 Å. There are two shorter (2.39 Å) and three longer (2.42 Å) Th–H bond lengths. In the sixth Th site, Th is bonded in a 4-coordinate geometry to four Al and four H atoms. There are two shorter (3.27 Å) and two longer (3.28 Å) Th–Al bond lengths. There are three shorter (2.40 Å) and one longer (2.41 Å) Th–H bond lengths. There are four inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to eight Th and two equivalent Al atoms. Both Al–Al bond lengths are 3.19 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to eight Th and two equivalent Al atoms. Both Al–Al bond lengths are 3.17 Å. In the third Al site, Al is bonded in a 10-coordinate geometry to eight Th and two Al atoms. The Al–Al bond length is 3.15 Å. In the fourth Al site, Al is bonded in a 10-coordinate geometry to eight Th and two Al atoms. There are nine inequivalent H sites. In the first H site, H is bonded to four Th atoms to form a mixture of corner, edge, and face-sharing HTh4 tetrahedra. In the second H site, H is bonded to four Th atoms to form a mixture of corner, edge, and face-sharing HTh4 tetrahedra. In the third H site, H is bonded to four equivalent Th atoms to form a mixture of corner and edge-sharing HTh4 tetrahedra. In the fourth H site, H is bonded to four Th atoms to form a mixture of corner and edge-sharing HTh4 tetrahedra. In the fifth H site, H is bonded to four Th atoms to form a mixture of corner and edge-sharing HTh4 tetrahedra. In the sixth H site, H is bonded to four Th atoms to form a mixture of corner and edge-sharing HTh4 tetrahedra. In the seventh H site, H is bonded to four Th atoms to form a mixture of corner, edge, and face-sharing HTh4 tetrahedra. In the eighth H site, H is bonded to four Th atoms to form a mixture of corner, edge, and face-sharing HTh4 tetrahedra. In the ninth H site, H is bonded to four Th atoms to form a mixture of corner and edge-sharing HTh4 tetrahedra.