La2NiAl7 crystallizes in the orthorhombic Imm2 space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 16-coordinate geometry to two equivalent Ni(2), two equivalent Al(6), two equivalent Al(7), two equivalent Al(8), four equivalent Al(3), and four equivalent Al(4) atoms. In the second La site, La(2) is bonded in a 16-coordinate geometry to two equivalent Ni(2), two equivalent Al(6), two equivalent Al(7), two equivalent Al(8), four equivalent Al(3), and four equivalent Al(4) atoms. In the third La site, La(3) is bonded in a 16-coordinate geometry to two equivalent Ni(1), two equivalent Al(1), two equivalent Al(2), two equivalent Al(5), four equivalent Al(3), and four equivalent Al(4) atoms. In the fourth La site, La(4) is bonded in a 16-coordinate geometry to two equivalent Ni(1), two equivalent Al(1), two equivalent Al(2), two equivalent Al(5), four equivalent Al(3), and four equivalent Al(4) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to two equivalent La(3), two equivalent La(4), one Al(1), and four equivalent Al(3) atoms. In the second Ni site, Ni(2) is bonded in a 5-coordinate geometry to two equivalent La(1), two equivalent La(2), one Al(7), and four equivalent Al(4) atoms. There are eight inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted single-bond geometry to two equivalent La(3), two equivalent La(4), and one Ni(1) atom. In the second Al site, Al(2) is bonded in a 9-coordinate geometry to two equivalent La(3), two equivalent La(4), one Al(5), and four equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a distorted single-bond geometry to one La(1), one La(2), one La(3), one La(4), one Ni(1), one Al(2), and one Al(8) atom. In the fourth Al site, Al(4) is bonded in a distorted single-bond geometry to one La(1), one La(2), one La(3), one La(4), one Ni(2), one Al(5), and one Al(6) atom. In the fifth Al site, Al(5) is bonded in a 9-coordinate geometry to two equivalent La(3), two equivalent La(4), one Al(2), and four equivalent Al(4) atoms. In the sixth Al site, Al(6) is bonded in a 9-coordinate geometry to two equivalent La(1), two equivalent La(2), one Al(8), and four equivalent Al(4) atoms. In the seventh Al site, Al(7) is bonded in a distorted single-bond geometry to two equivalent La(1), two equivalent La(2), and one Ni(2) atom. In the eighth Al site, Al(8) is bonded in a 9-coordinate geometry to two equivalent La(1), two equivalent La(2), one Al(6), and four equivalent Al(3) atoms.
La2NiAl7 crystallizes in the orthorhombic Imm2 space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 16-coordinate geometry to two equivalent Ni(2), two equivalent Al(6), two equivalent Al(7), two equivalent Al(8), four equivalent Al(3), and four equivalent Al(4) atoms. Both La(1)-Ni(2) bond lengths are 3.39 Å. Both La(1)-Al(6) bond lengths are 3.38 Å. Both La(1)-Al(7) bond lengths are 3.20 Å. Both La(1)-Al(8) bond lengths are 3.28 Å. All La(1)-Al(3) bond lengths are 3.51 Å. All La(1)-Al(4) bond lengths are 3.43 Å. In the second La site, La(2) is bonded in a 16-coordinate geometry to two equivalent Ni(2), two equivalent Al(6), two equivalent Al(7), two equivalent Al(8), four equivalent Al(3), and four equivalent Al(4) atoms. Both La(2)-Ni(2) bond lengths are 3.36 Å. Both La(2)-Al(6) bond lengths are 3.35 Å. Both La(2)-Al(7) bond lengths are 3.22 Å. Both La(2)-Al(8) bond lengths are 3.30 Å. All La(2)-Al(3) bond lengths are 3.41 Å. All La(2)-Al(4) bond lengths are 3.46 Å. In the third La site, La(3) is bonded in a 16-coordinate geometry to two equivalent Ni(1), two equivalent Al(1), two equivalent Al(2), two equivalent Al(5), four equivalent Al(3), and four equivalent Al(4) atoms. Both La(3)-Ni(1) bond lengths are 3.38 Å. Both La(3)-Al(1) bond lengths are 3.21 Å. Both La(3)-Al(2) bond lengths are 3.35 Å. Both La(3)-Al(5) bond lengths are 3.30 Å. All La(3)-Al(3) bond lengths are 3.46 Å. All La(3)-Al(4) bond lengths are 3.39 Å. In the fourth La site, La(4) is bonded in a 16-coordinate geometry to two equivalent Ni(1), two equivalent Al(1), two equivalent Al(2), two equivalent Al(5), four equivalent Al(3), and four equivalent Al(4) atoms. Both La(4)-Ni(1) bond lengths are 3.40 Å. Both La(4)-Al(1) bond lengths are 3.20 Å. Both La(4)-Al(2) bond lengths are 3.36 Å. Both La(4)-Al(5) bond lengths are 3.29 Å. All La(4)-Al(3) bond lengths are 3.43 Å. All La(4)-Al(4) bond lengths are 3.53 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to two equivalent La(3), two equivalent La(4), one Al(1), and four equivalent Al(3) atoms. The Ni(1)-Al(1) bond length is 2.36 Å. All Ni(1)-Al(3) bond lengths are 2.40 Å. In the second Ni site, Ni(2) is bonded in a 5-coordinate geometry to two equivalent La(1), two equivalent La(2), one Al(7), and four equivalent Al(4) atoms. The Ni(2)-Al(7) bond length is 2.35 Å. All Ni(2)-Al(4) bond lengths are 2.40 Å. There are eight inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted single-bond geometry to two equivalent La(3), two equivalent La(4), and one Ni(1) atom. In the second Al site, Al(2) is bonded in a 9-coordinate geometry to two equivalent La(3), two equivalent La(4), one Al(5), and four equivalent Al(3) atoms. The Al(2)-Al(5) bond length is 2.54 Å. All Al(2)-Al(3) bond lengths are 2.65 Å. In the third Al site, Al(3) is bonded in a distorted single-bond geometry to one La(1), one La(2), one La(3), one La(4), one Ni(1), one Al(2), and one Al(8) atom. The Al(3)-Al(8) bond length is 2.69 Å. In the fourth Al site, Al(4) is bonded in a distorted single-bond geometry to one La(1), one La(2), one La(3), one La(4), one Ni(2), one Al(5), and one Al(6) atom. The Al(4)-Al(5) bond length is 2.69 Å. The Al(4)-Al(6) bond length is 2.65 Å. In the fifth Al site, Al(5) is bonded in a 9-coordinate geometry to two equivalent La(3), two equivalent La(4), one Al(2), and four equivalent Al(4) atoms. In the sixth Al site, Al(6) is bonded in a 9-coordinate geometry to two equivalent La(1), two equivalent La(2), one Al(8), and four equivalent Al(4) atoms. The Al(6)-Al(8) bond length is 2.55 Å. In the seventh Al site, Al(7) is bonded in a distorted single-bond geometry to two equivalent La(1), two equivalent La(2), and one Ni(2) atom. In the eighth Al site, Al(8) is bonded in a 9-coordinate geometry to two equivalent La(1), two equivalent La(2), one Al(6), and four equivalent Al(3) atoms.