MgNb2V2O8 is Ilmenite-derived structured and crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Nb(1)O6 pentagonal pyramids, edges with four equivalent V(1)O6 octahedra, and faces with two equivalent Nb(1)O6 pentagonal pyramids. Nb(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted NbO6 pentagonal pyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with eight equivalent V(1)O6 octahedra, edges with two equivalent Nb(1)O6 pentagonal pyramids, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-71°. V(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form VO6 octahedra that share corners with eight equivalent Nb(1)O6 pentagonal pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent V(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent V(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Nb(1), and one V(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Nb(1), and one V(1) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Nb(1), and two equivalent V(1) atoms.
MgNb2V2O8 is Ilmenite-derived structured and crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Nb(1)O6 pentagonal pyramids, edges with four equivalent V(1)O6 octahedra, and faces with two equivalent Nb(1)O6 pentagonal pyramids. Both Mg(1)-O(2) bond lengths are 2.11 Å. Both Mg(1)-O(3) bond lengths are 2.10 Å. Both Mg(1)-O(4) bond lengths are 1.97 Å. Nb(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted NbO6 pentagonal pyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with eight equivalent V(1)O6 octahedra, edges with two equivalent Nb(1)O6 pentagonal pyramids, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-71°. The Nb(1)-O(1) bond length is 1.92 Å. The Nb(1)-O(4) bond length is 2.08 Å. There is one shorter (1.97 Å) and one longer (2.26 Å) Nb(1)-O(2) bond length. There is one shorter (1.97 Å) and one longer (2.26 Å) Nb(1)-O(3) bond length. V(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form VO6 octahedra that share corners with eight equivalent Nb(1)O6 pentagonal pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent V(1)O6 octahedra. The V(1)-O(2) bond length is 2.22 Å. The V(1)-O(3) bond length is 2.23 Å. There is one shorter (2.10 Å) and one longer (2.11 Å) V(1)-O(1) bond length. There is one shorter (2.15 Å) and one longer (2.16 Å) V(1)-O(4) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent V(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Nb(1), and one V(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Nb(1), and one V(1) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Nb(1), and two equivalent V(1) atoms.