Ba2Ni3AlO7 crystallizes in the orthorhombic Pmmm space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted corner-sharing NiO5 square pyramids. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(4) atoms. Al(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Ni(2) atoms to form a mixture of distorted face, corner, and edge-sharing OBa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), and two equivalent Al(1) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), and two equivalent Al(1) atoms. In the fourth O site, O(4) is bonded to four equivalent Ba(1), one Ni(1), and one Ni(2) atom to form a mixture of distorted face, corner, and edge-sharing OBa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°.
Ba2Ni3AlO7 crystallizes in the orthorhombic Pmmm space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Both Ba(1)-O(1) bond lengths are 2.84 Å. Both Ba(1)-O(2) bond lengths are 3.01 Å. Both Ba(1)-O(3) bond lengths are 2.96 Å. All Ba(1)-O(4) bond lengths are 2.72 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted corner-sharing NiO5 square pyramids. The Ni(1)-O(4) bond length is 2.11 Å. Both Ni(1)-O(2) bond lengths are 1.92 Å. Both Ni(1)-O(3) bond lengths are 2.00 Å. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(4) atoms. Both Ni(2)-O(1) bond lengths are 1.96 Å. Both Ni(2)-O(4) bond lengths are 1.89 Å. Al(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. All Al(1)-O(2) bond lengths are 2.32 Å. All Al(1)-O(3) bond lengths are 2.25 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Ni(2) atoms to form a mixture of distorted face, corner, and edge-sharing OBa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), and two equivalent Al(1) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), and two equivalent Al(1) atoms. In the fourth O site, O(4) is bonded to four equivalent Ba(1), one Ni(1), and one Ni(2) atom to form a mixture of distorted face, corner, and edge-sharing OBa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-67°.