TaFeAl crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Fe(3); two equivalent Fe(1); two equivalent Fe(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the second Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2); three Ta(1,1); one Fe(1); two equivalent Fe(3); four equivalent Fe(2); two equivalent Al(2); and three equivalent Al(1) atoms. In the third Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Fe(1), two equivalent Fe(3), four equivalent Fe(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the fourth Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Fe(3); two equivalent Fe(1); two equivalent Fe(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the fifth Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Fe(3); two equivalent Fe(1); two equivalent Fe(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the sixth Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2); three Ta(1,1); one Fe(1); two equivalent Fe(3); four equivalent Fe(2); two equivalent Al(2); and three equivalent Al(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two Ta(2,2); four Ta(1,1); two equivalent Al(1); and four equivalent Al(2) atoms to form distorted FeTa6Al6 cuboctahedra that share corners with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with eight equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, edges with two equivalent Fe(1)Ta6Al6 cuboctahedra, edges with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, faces with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra, and faces with eight equivalent Al(2)Ta6Al4Fe2 cuboctahedra. In the second Fe site, Fe(2) is bonded to two Ta(1,1); four Ta(2,2,2); two equivalent Fe(2); two equivalent Fe(3); and two equivalent Al(1) atoms to form distorted FeTa6Al2Fe4 cuboctahedra that share corners with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with six equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with two equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, edges with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, faces with two equivalent Fe(1)Ta6Al6 cuboctahedra, faces with two equivalent Al(2)Ta6Al4Fe2 cuboctahedra, faces with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, and faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra. In the third Fe site, Fe(3) is bonded to two Ta(1,1); four Ta(2,2); four equivalent Fe(2); and two equivalent Al(1) atoms to form distorted FeTa6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with eight equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, edges with four equivalent Fe(1)Ta6Al6 cuboctahedra, faces with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra, and faces with eight equivalent Fe(2)Ta6Al2Fe4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three Ta(1,1); three Ta(2,2); one Fe(1); one Fe(3); two equivalent Fe(2); and two equivalent Al(2) atoms to form distorted AlTa6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with two equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra, faces with two equivalent Al(1)Ta6Al2Fe4 cuboctahedra, faces with three equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, faces with three equivalent Fe(1)Ta6Al6 cuboctahedra, faces with six equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, and faces with six equivalent Al(2)Ta6Al4Fe2 cuboctahedra. In the second Al site, Al(2) is bonded to two Ta(2,2); four Ta(1,1,1); two equivalent Fe(1); two equivalent Al(1); and two equivalent Al(2) atoms to form distorted AlTa6Al4Fe2 cuboctahedra that share corners with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, corners with six equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, edges with two equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with two equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, faces with four equivalent Fe(1)Ta6Al6 cuboctahedra, faces with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, and faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra.
TaFeAl crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Fe(3); two equivalent Fe(1); two equivalent Fe(2); three equivalent Al(1); and four equivalent Al(2) atoms. The Ta(1)-Ta(1) bond length is 3.16 Å. There is one shorter (2.98 Å) and two longer (3.02 Å) Ta(1)-Ta(2,2) bond lengths. The Ta(1)-Fe(3) bond length is 2.81 Å. Both Ta(1)-Fe(1) bond lengths are 2.94 Å. Both Ta(1)-Fe(2) bond lengths are 2.79 Å. There are two shorter (2.86 Å) and one longer (2.93 Å) Ta(1)-Al(1) bond length. There are two shorter (2.90 Å) and two longer (2.93 Å) Ta(1)-Al(2) bond lengths. In the second Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2); three Ta(1,1); one Fe(1); two equivalent Fe(3); four equivalent Fe(2); two equivalent Al(2); and three equivalent Al(1) atoms. The Ta(2)-Ta(2) bond length is 2.90 Å. Both Ta(2)-Ta(1) bond lengths are 3.02 Å. The Ta(2)-Fe(1) bond length is 2.94 Å. Both Ta(2)-Fe(3) bond lengths are 2.87 Å. There are two shorter (2.84 Å) and two longer (2.86 Å) Ta(2)-Fe(2) bond lengths. Both Ta(2)-Al(2) bond lengths are 2.91 Å. There is one shorter (2.81 Å) and two longer (2.92 Å) Ta(2)-Al(1) bond lengths. In the third Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Fe(1), two equivalent Fe(3), four equivalent Fe(2), two equivalent Al(2), and three equivalent Al(1) atoms. There is one shorter (2.98 Å) and two longer (3.02 Å) Ta(2)-Ta(1) bond lengths. The Ta(2)-Fe(1) bond length is 2.94 Å. Both Ta(2)-Fe(3) bond lengths are 2.87 Å. There are two shorter (2.84 Å) and two longer (2.86 Å) Ta(2)-Fe(2) bond lengths. Both Ta(2)-Al(2) bond lengths are 2.91 Å. There is one shorter (2.81 Å) and two longer (2.92 Å) Ta(2)-Al(1) bond lengths. In the fourth Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Fe(3); two equivalent Fe(1); two equivalent Fe(2); three equivalent Al(1); and four equivalent Al(2) atoms. Both Ta(1)-Ta(2) bond lengths are 3.02 Å. The Ta(1)-Fe(3) bond length is 2.81 Å. Both Ta(1)-Fe(1) bond lengths are 2.94 Å. Both Ta(1)-Fe(2) bond lengths are 2.79 Å. There are two shorter (2.86 Å) and one longer (2.93 Å) Ta(1)-Al(1) bond length. There are two shorter (2.90 Å) and two longer (2.93 Å) Ta(1)-Al(2) bond lengths. In the fifth Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Fe(3); two equivalent Fe(1); two equivalent Fe(2); three equivalent Al(1); and four equivalent Al(2) atoms. The Ta(1)-Ta(1) bond length is 3.16 Å. The Ta(1)-Ta(2) bond length is 2.98 Å. The Ta(1)-Fe(3) bond length is 2.81 Å. Both Ta(1)-Fe(1) bond lengths are 2.94 Å. Both Ta(1)-Fe(2) bond lengths are 2.79 Å. There are two shorter (2.86 Å) and one longer (2.93 Å) Ta(1)-Al(1) bond length. There are two shorter (2.90 Å) and two longer (2.93 Å) Ta(1)-Al(2) bond lengths. In the sixth Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2); three Ta(1,1); one Fe(1); two equivalent Fe(3); four equivalent Fe(2); two equivalent Al(2); and three equivalent Al(1) atoms. The Ta(2)-Ta(2) bond length is 2.90 Å. The Ta(2)-Fe(1) bond length is 2.94 Å. Both Ta(2)-Fe(3) bond lengths are 2.87 Å. There are two shorter (2.84 Å) and two longer (2.86 Å) Ta(2)-Fe(2) bond lengths. Both Ta(2)-Al(2) bond lengths are 2.91 Å. There is one shorter (2.81 Å) and two longer (2.92 Å) Ta(2)-Al(1) bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two Ta(2,2); four Ta(1,1); two equivalent Al(1); and four equivalent Al(2) atoms to form distorted FeTa6Al6 cuboctahedra that share corners with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with eight equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, edges with two equivalent Fe(1)Ta6Al6 cuboctahedra, edges with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, faces with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra, and faces with eight equivalent Al(2)Ta6Al4Fe2 cuboctahedra. Both Fe(1)-Al(1) bond lengths are 2.47 Å. There are two shorter (2.40 Å) and two longer (2.50 Å) Fe(1)-Al(2) bond lengths. In the second Fe site, Fe(2) is bonded to two Ta(1,1); four Ta(2,2,2); two equivalent Fe(2); two equivalent Fe(3); and two equivalent Al(1) atoms to form distorted FeTa6Al2Fe4 cuboctahedra that share corners with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with six equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with two equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, edges with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, faces with two equivalent Fe(1)Ta6Al6 cuboctahedra, faces with two equivalent Al(2)Ta6Al4Fe2 cuboctahedra, faces with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, and faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra. There is one shorter (2.38 Å) and one longer (2.57 Å) Fe(2)-Fe(2) bond length. There is one shorter (2.36 Å) and one longer (2.54 Å) Fe(2)-Fe(3) bond length. Both Fe(2)-Al(1) bond lengths are 2.44 Å. In the third Fe site, Fe(3) is bonded to two Ta(1,1); four Ta(2,2); four equivalent Fe(2); and two equivalent Al(1) atoms to form distorted FeTa6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with eight equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, edges with four equivalent Fe(1)Ta6Al6 cuboctahedra, faces with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra, and faces with eight equivalent Fe(2)Ta6Al2Fe4 cuboctahedra. Both Fe(3)-Al(1) bond lengths are 2.46 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three Ta(1,1); three Ta(2,2); one Fe(1); one Fe(3); two equivalent Fe(2); and two equivalent Al(2) atoms to form distorted AlTa6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with two equivalent Fe(1)Ta6Al6 cuboctahedra, corners with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra, faces with two equivalent Al(1)Ta6Al2Fe4 cuboctahedra, faces with three equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, faces with three equivalent Fe(1)Ta6Al6 cuboctahedra, faces with six equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, and faces with six equivalent Al(2)Ta6Al4Fe2 cuboctahedra. Both Al(1)-Al(2) bond lengths are 2.57 Å. In the second Al site, Al(2) is bonded to two Ta(2,2); four Ta(1,1,1); two equivalent Fe(1); two equivalent Al(1); and two equivalent Al(2) atoms to form distorted AlTa6Al4Fe2 cuboctahedra that share corners with four equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Ta6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, corners with six equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, edges with two equivalent Al(2)Ta6Al4Fe2 cuboctahedra, edges with four equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with two equivalent Fe(2)Ta6Al2Fe4 cuboctahedra, faces with two equivalent Fe(3)Ta6Al2Fe4 cuboctahedra, faces with four equivalent Fe(1)Ta6Al6 cuboctahedra, faces with four equivalent Al(2)Ta6Al4Fe2 cuboctahedra, and faces with six equivalent Al(1)Ta6Al2Fe4 cuboctahedra. There is one shorter (2.40 Å) and one longer (2.55 Å) Al(2)-Al(2) bond length.