Nb12GaAl3 crystallizes in the orthorhombic Pmmm space group. There are five inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 14-coordinate geometry to one Nb(1), one Nb(2), four equivalent Nb(4), four equivalent Nb(5), two equivalent Ga(1), and two equivalent Al(1) atoms. In the second Nb site, Nb(2) is bonded in a 14-coordinate geometry to one Nb(1), one Nb(2), four equivalent Nb(3), four equivalent Nb(5), two equivalent Al(1), and two equivalent Al(2) atoms. In the third Nb site, Nb(3) is bonded in a 14-coordinate geometry to two equivalent Nb(3), four equivalent Nb(2), four equivalent Nb(5), two equivalent Al(1), and two equivalent Al(2) atoms. In the fourth Nb site, Nb(4) is bonded in a 14-coordinate geometry to two equivalent Nb(4), four equivalent Nb(1), four equivalent Nb(5), two equivalent Ga(1), and two equivalent Al(1) atoms. In the fifth Nb site, Nb(5) is bonded in a 14-coordinate geometry to two equivalent Nb(1), two equivalent Nb(2), two equivalent Nb(3), two equivalent Nb(4), two equivalent Nb(5), one Ga(1), one Al(2), and two equivalent Al(1) atoms. Ga(1) is bonded to four equivalent Nb(1), four equivalent Nb(4), and four equivalent Nb(5) atoms to form GaNb12 cuboctahedra that share edges with two equivalent Al(2)Nb12 cuboctahedra, edges with four equivalent Ga(1)Nb12 cuboctahedra, and faces with eight equivalent Al(1)Nb12 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(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 AlNb12 cuboctahedra that share edges with six equivalent Al(1)Nb12 cuboctahedra, faces with four equivalent Ga(1)Nb12 cuboctahedra, and faces with four equivalent Al(2)Nb12 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Nb(2), four equivalent Nb(3), and four equivalent Nb(5) atoms to form AlNb12 cuboctahedra that share edges with two equivalent Ga(1)Nb12 cuboctahedra, edges with four equivalent Al(2)Nb12 cuboctahedra, and faces with eight equivalent Al(1)Nb12 cuboctahedra.
Nb12GaAl3 crystallizes in the orthorhombic Pmmm space group. There are five inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 14-coordinate geometry to one Nb(1), one Nb(2), four equivalent Nb(4), four equivalent Nb(5), two equivalent Ga(1), and two equivalent Al(1) atoms. The Nb(1)-Nb(1) bond length is 2.60 Å. The Nb(1)-Nb(2) bond length is 2.59 Å. All Nb(1)-Nb(4) bond lengths are 3.18 Å. All Nb(1)-Nb(5) bond lengths are 3.19 Å. Both Nb(1)-Ga(1) bond lengths are 2.91 Å. Both Nb(1)-Al(1) bond lengths are 2.91 Å. In the second Nb site, Nb(2) is bonded in a 14-coordinate geometry to one Nb(1), one Nb(2), four equivalent Nb(3), four equivalent Nb(5), two equivalent Al(1), and two equivalent Al(2) atoms. The Nb(2)-Nb(2) bond length is 2.61 Å. All Nb(2)-Nb(3) bond lengths are 3.19 Å. All Nb(2)-Nb(5) bond lengths are 3.19 Å. Both Nb(2)-Al(1) bond lengths are 2.91 Å. Both Nb(2)-Al(2) bond lengths are 2.91 Å. In the third Nb site, Nb(3) is bonded in a 14-coordinate geometry to two equivalent Nb(3), four equivalent Nb(2), four equivalent Nb(5), two equivalent Al(1), and two equivalent Al(2) atoms. There is one shorter (2.60 Å) and one longer (2.61 Å) Nb(3)-Nb(3) bond length. All Nb(3)-Nb(5) bond lengths are 3.18 Å. Both Nb(3)-Al(1) bond lengths are 2.91 Å. Both Nb(3)-Al(2) bond lengths are 2.91 Å. In the fourth Nb site, Nb(4) is bonded in a 14-coordinate geometry to two equivalent Nb(4), four equivalent Nb(1), four equivalent Nb(5), two equivalent Ga(1), and two equivalent Al(1) atoms. There is one shorter (2.59 Å) and one longer (2.62 Å) Nb(4)-Nb(4) bond length. All Nb(4)-Nb(5) bond lengths are 3.19 Å. Both Nb(4)-Ga(1) bond lengths are 2.91 Å. Both Nb(4)-Al(1) bond lengths are 2.90 Å. In the fifth Nb site, Nb(5) is bonded in a 14-coordinate geometry to two equivalent Nb(1), two equivalent Nb(2), two equivalent Nb(3), two equivalent Nb(4), two equivalent Nb(5), one Ga(1), one Al(2), and two equivalent Al(1) atoms. There is one shorter (2.59 Å) and one longer (2.62 Å) Nb(5)-Nb(5) bond length. The Nb(5)-Ga(1) bond length is 2.91 Å. The Nb(5)-Al(2) bond length is 2.91 Å. Both Nb(5)-Al(1) bond lengths are 2.91 Å. Ga(1) is bonded to four equivalent Nb(1), four equivalent Nb(4), and four equivalent Nb(5) atoms to form GaNb12 cuboctahedra that share edges with two equivalent Al(2)Nb12 cuboctahedra, edges with four equivalent Ga(1)Nb12 cuboctahedra, and faces with eight equivalent Al(1)Nb12 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(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 AlNb12 cuboctahedra that share edges with six equivalent Al(1)Nb12 cuboctahedra, faces with four equivalent Ga(1)Nb12 cuboctahedra, and faces with four equivalent Al(2)Nb12 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Nb(2), four equivalent Nb(3), and four equivalent Nb(5) atoms to form AlNb12 cuboctahedra that share edges with two equivalent Ga(1)Nb12 cuboctahedra, edges with four equivalent Al(2)Nb12 cuboctahedra, and faces with eight equivalent Al(1)Nb12 cuboctahedra.