MgNbCrO4 crystallizes in the monoclinic P2/m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra and edges with four equivalent Nb(1)O6 octahedra. Nb(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NbO6 octahedra that share edges with two equivalent Nb(1)O6 octahedra and edges with four equivalent Mg(1)O6 octahedra. Cr(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Nb(1), and two equivalent Cr(1) atoms to form a mixture of edge and corner-sharing OMg2NbCr2 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Nb(1) atoms.
MgNbCrO4 crystallizes in the monoclinic P2/m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra and edges with four equivalent Nb(1)O6 octahedra. Both Mg(1)-O(2) bond lengths are 2.03 Å. All Mg(1)-O(1) bond lengths are 2.18 Å. Nb(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NbO6 octahedra that share edges with two equivalent Nb(1)O6 octahedra and edges with four equivalent Mg(1)O6 octahedra. Both Nb(1)-O(1) bond lengths are 2.16 Å. All Nb(1)-O(2) bond lengths are 2.05 Å. Cr(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. All Cr(1)-O(1) bond lengths are 2.12 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Nb(1), and two equivalent Cr(1) atoms to form a mixture of edge and corner-sharing OMg2NbCr2 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Nb(1) atoms.