ScFeAl crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 12-coordinate geometry to three equivalent Sc(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 Sc site, Sc(2) is bonded in a 16-coordinate geometry to one Sc(2), three equivalent Sc(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 equivalent Sc(2), four equivalent Sc(1), two equivalent Al(1), and four equivalent Al(2) atoms to form distorted FeSc6Al6 cuboctahedra that share corners with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with eight equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, edges with two equivalent Fe(1)Sc6Al6 cuboctahedra, edges with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, faces with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra, and faces with eight equivalent Al(2)Sc6Al4Fe2 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Sc(1), four equivalent Sc(2), two equivalent Fe(2), two equivalent Fe(3), and two equivalent Al(1) atoms to form distorted FeSc6Al2Fe4 cuboctahedra that share corners with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with six equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with two equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, edges with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, faces with two equivalent Fe(1)Sc6Al6 cuboctahedra, faces with two equivalent Al(2)Sc6Al4Fe2 cuboctahedra, faces with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, and faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra. In the third Fe site, Fe(3) is bonded to two equivalent Sc(1), four equivalent Sc(2), four equivalent Fe(2), and two equivalent Al(1) atoms to form distorted FeSc6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with eight equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, edges with four equivalent Fe(1)Sc6Al6 cuboctahedra, faces with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra, and faces with eight equivalent Fe(2)Sc6Al2Fe4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Sc(1), three equivalent Sc(2), one Fe(1), one Fe(3), two equivalent Fe(2), and two equivalent Al(2) atoms to form distorted AlSc6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with two equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra, faces with two equivalent Al(1)Sc6Al2Fe4 cuboctahedra, faces with three equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, faces with three equivalent Fe(1)Sc6Al6 cuboctahedra, faces with six equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, and faces with six equivalent Al(2)Sc6Al4Fe2 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent Sc(2), four equivalent Sc(1), two equivalent Fe(1), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted AlSc6Al4Fe2 cuboctahedra that share corners with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, corners with six equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, edges with two equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with two equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, faces with four equivalent Fe(1)Sc6Al6 cuboctahedra, faces with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, and faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra.
ScFeAl crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 12-coordinate geometry to three equivalent Sc(2), one Fe(3), two equivalent Fe(1), two equivalent Fe(2), three equivalent Al(1), and four equivalent Al(2) atoms. All Sc(1)-Sc(2) bond lengths are 3.17 Å. The Sc(1)-Fe(3) bond length is 2.93 Å. Both Sc(1)-Fe(1) bond lengths are 3.08 Å. Both Sc(1)-Fe(2) bond lengths are 2.92 Å. There are two shorter (3.01 Å) and one longer (3.06 Å) Sc(1)-Al(1) bond length. There are two shorter (3.03 Å) and two longer (3.08 Å) Sc(1)-Al(2) bond lengths. In the second Sc site, Sc(2) is bonded in a 16-coordinate geometry to one Sc(2), three equivalent Sc(1), one Fe(1), two equivalent Fe(3), four equivalent Fe(2), two equivalent Al(2), and three equivalent Al(1) atoms. The Sc(2)-Sc(2) bond length is 2.97 Å. The Sc(2)-Fe(1) bond length is 3.09 Å. Both Sc(2)-Fe(3) bond lengths are 2.99 Å. All Sc(2)-Fe(2) bond lengths are 2.97 Å. Both Sc(2)-Al(2) bond lengths are 3.10 Å. There is one shorter (2.91 Å) and two longer (3.08 Å) Sc(2)-Al(1) bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Sc(2), four equivalent Sc(1), two equivalent Al(1), and four equivalent Al(2) atoms to form distorted FeSc6Al6 cuboctahedra that share corners with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with eight equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, edges with two equivalent Fe(1)Sc6Al6 cuboctahedra, edges with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, faces with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra, and faces with eight equivalent Al(2)Sc6Al4Fe2 cuboctahedra. Both Fe(1)-Al(1) bond lengths are 2.62 Å. There are two shorter (2.52 Å) and two longer (2.62 Å) Fe(1)-Al(2) bond lengths. In the second Fe site, Fe(2) is bonded to two equivalent Sc(1), four equivalent Sc(2), two equivalent Fe(2), two equivalent Fe(3), and two equivalent Al(1) atoms to form distorted FeSc6Al2Fe4 cuboctahedra that share corners with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with six equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with two equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, edges with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, faces with two equivalent Fe(1)Sc6Al6 cuboctahedra, faces with two equivalent Al(2)Sc6Al4Fe2 cuboctahedra, faces with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, and faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra. There is one shorter (2.44 Å) and one longer (2.77 Å) Fe(2)-Fe(2) bond length. There is one shorter (2.47 Å) and one longer (2.67 Å) Fe(2)-Fe(3) bond length. Both Fe(2)-Al(1) bond lengths are 2.54 Å. In the third Fe site, Fe(3) is bonded to two equivalent Sc(1), four equivalent Sc(2), four equivalent Fe(2), and two equivalent Al(1) atoms to form distorted FeSc6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with eight equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, edges with four equivalent Fe(1)Sc6Al6 cuboctahedra, faces with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra, and faces with eight equivalent Fe(2)Sc6Al2Fe4 cuboctahedra. Both Fe(3)-Al(1) bond lengths are 2.56 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Sc(1), three equivalent Sc(2), one Fe(1), one Fe(3), two equivalent Fe(2), and two equivalent Al(2) atoms to form distorted AlSc6Al2Fe4 cuboctahedra that share corners with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with two equivalent Fe(1)Sc6Al6 cuboctahedra, corners with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra, faces with two equivalent Al(1)Sc6Al2Fe4 cuboctahedra, faces with three equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, faces with three equivalent Fe(1)Sc6Al6 cuboctahedra, faces with six equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, and faces with six equivalent Al(2)Sc6Al4Fe2 cuboctahedra. Both Al(1)-Al(2) bond lengths are 2.70 Å. In the second Al site, Al(2) is bonded to two equivalent Sc(2), four equivalent Sc(1), two equivalent Fe(1), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted AlSc6Al4Fe2 cuboctahedra that share corners with four equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(1)Sc6Al2Fe4 cuboctahedra, corners with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, corners with six equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, edges with two equivalent Al(2)Sc6Al4Fe2 cuboctahedra, edges with four equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with two equivalent Fe(2)Sc6Al2Fe4 cuboctahedra, faces with two equivalent Fe(3)Sc6Al2Fe4 cuboctahedra, faces with four equivalent Fe(1)Sc6Al6 cuboctahedra, faces with four equivalent Al(2)Sc6Al4Fe2 cuboctahedra, and faces with six equivalent Al(1)Sc6Al2Fe4 cuboctahedra. There is one shorter (2.56 Å) and one longer (2.64 Å) Al(2)-Al(2) bond length.