Nb12Sn3Sb crystallizes in the orthorhombic Pmmm space group. There are five inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one Nb(1), one Nb(2), two equivalent Sn(1), and two equivalent Sb(1) atoms. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one Nb(1), one Nb(2), two equivalent Sn(1), and two equivalent Sn(2) atoms. In the third Nb site, Nb(3) is bonded in a 6-coordinate geometry to two equivalent Nb(3), two equivalent Sn(1), and two equivalent Sn(2) atoms. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to two equivalent Nb(4), two equivalent Sn(1), and two equivalent Sb(1) atoms. In the fifth Nb site, Nb(5) is bonded in a 6-coordinate geometry to two equivalent Nb(5), one Sn(2), two equivalent Sn(1), and one Sb(1) atom. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to two equivalent Nb(1), two equivalent Nb(2), two equivalent Nb(3), two equivalent Nb(4), and four equivalent Nb(5) atoms to form SnNb12 cuboctahedra that share edges with six equivalent Sn(1)Nb12 cuboctahedra, faces with four equivalent Sn(2)Nb12 cuboctahedra, and faces with four equivalent Sb(1)Nb12 cuboctahedra. In the second Sn site, Sn(2) is bonded to four equivalent Nb(2), four equivalent Nb(3), and four equivalent Nb(5) atoms to form SnNb12 cuboctahedra that share edges with two equivalent Sb(1)Nb12 cuboctahedra, edges with four equivalent Sn(2)Nb12 cuboctahedra, and faces with eight equivalent Sn(1)Nb12 cuboctahedra. Sb(1) is bonded to four equivalent Nb(1), four equivalent Nb(4), and four equivalent Nb(5) atoms to form SbNb12 cuboctahedra that share edges with two equivalent Sn(2)Nb12 cuboctahedra, edges with four equivalent Sb(1)Nb12 cuboctahedra, and faces with eight equivalent Sn(1)Nb12 cuboctahedra.
Nb12Sn3Sb crystallizes in the orthorhombic Pmmm space group. There are five inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one Nb(1), one Nb(2), two equivalent Sn(1), and two equivalent Sb(1) atoms. The Nb(1)-Nb(1) bond length is 2.63 Å. The Nb(1)-Nb(2) bond length is 2.69 Å. Both Nb(1)-Sn(1) bond lengths are 2.98 Å. Both Nb(1)-Sb(1) bond lengths are 2.97 Å. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one Nb(1), one Nb(2), two equivalent Sn(1), and two equivalent Sn(2) atoms. The Nb(2)-Nb(2) bond length is 2.63 Å. Both Nb(2)-Sn(1) bond lengths are 2.98 Å. Both Nb(2)-Sn(2) bond lengths are 2.97 Å. In the third Nb site, Nb(3) is bonded in a 6-coordinate geometry to two equivalent Nb(3), two equivalent Sn(1), and two equivalent Sn(2) atoms. There is one shorter (2.66 Å) and one longer (2.67 Å) Nb(3)-Nb(3) bond length. Both Nb(3)-Sn(1) bond lengths are 2.98 Å. Both Nb(3)-Sn(2) bond lengths are 2.97 Å. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to two equivalent Nb(4), two equivalent Sn(1), and two equivalent Sb(1) atoms. There is one shorter (2.63 Å) and one longer (2.69 Å) Nb(4)-Nb(4) bond length. Both Nb(4)-Sn(1) bond lengths are 2.98 Å. Both Nb(4)-Sb(1) bond lengths are 2.96 Å. In the fifth Nb site, Nb(5) is bonded in a 6-coordinate geometry to two equivalent Nb(5), one Sn(2), two equivalent Sn(1), and one Sb(1) atom. There is one shorter (2.64 Å) and one longer (2.68 Å) Nb(5)-Nb(5) bond length. The Nb(5)-Sn(2) bond length is 2.98 Å. Both Nb(5)-Sn(1) bond lengths are 2.98 Å. The Nb(5)-Sb(1) bond length is 2.96 Å. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to two equivalent Nb(1), two equivalent Nb(2), two equivalent Nb(3), two equivalent Nb(4), and four equivalent Nb(5) atoms to form SnNb12 cuboctahedra that share edges with six equivalent Sn(1)Nb12 cuboctahedra, faces with four equivalent Sn(2)Nb12 cuboctahedra, and faces with four equivalent Sb(1)Nb12 cuboctahedra. In the second Sn site, Sn(2) is bonded to four equivalent Nb(2), four equivalent Nb(3), and four equivalent Nb(5) atoms to form SnNb12 cuboctahedra that share edges with two equivalent Sb(1)Nb12 cuboctahedra, edges with four equivalent Sn(2)Nb12 cuboctahedra, and faces with eight equivalent Sn(1)Nb12 cuboctahedra. Sb(1) is bonded to four equivalent Nb(1), four equivalent Nb(4), and four equivalent Nb(5) atoms to form SbNb12 cuboctahedra that share edges with two equivalent Sn(2)Nb12 cuboctahedra, edges with four equivalent Sb(1)Nb12 cuboctahedra, and faces with eight equivalent Sn(1)Nb12 cuboctahedra.