MgCr2(NiO4)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Cr(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form edge-sharing NiO6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form edge-sharing NiO6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Ni(1), and one Ni(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Ni(1), and one Ni(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cr(1) and one Ni(1) atom.
MgCr2(NiO4)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Both Mg(1)-O(1) bond lengths are 2.08 Å. Both Mg(1)-O(2) bond lengths are 2.05 Å. Both Mg(1)-O(3) bond lengths are 2.42 Å. Cr(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Cr(1)-O(1) bond length is 1.85 Å. The Cr(1)-O(2) bond length is 1.86 Å. The Cr(1)-O(3) bond length is 1.67 Å. The Cr(1)-O(4) bond length is 1.65 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form edge-sharing NiO6 octahedra. Both Ni(1)-O(1) bond lengths are 2.15 Å. Both Ni(1)-O(2) bond lengths are 2.11 Å. Both Ni(1)-O(4) bond lengths are 2.08 Å. In the second Ni site, Ni(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form edge-sharing NiO6 octahedra. Both Ni(2)-O(1) bond lengths are 2.16 Å. Both Ni(2)-O(2) bond lengths are 2.14 Å. Both Ni(2)-O(3) bond lengths are 2.03 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Ni(1), and one Ni(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(1), one Ni(1), and one Ni(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cr(1) and one Ni(1) atom.