MgV3(OF)4 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one F(1), one F(4), two equivalent F(2), and two equivalent F(3) atoms to form MgF6 octahedra that share corners with two equivalent V(2)O3F3 octahedra, corners with three equivalent V(1)O3F3 octahedra,  an edgeedge with one V(1)O3F3 octahedra, edges with two equivalent Mg(1)F6 octahedra, and  a faceface with one V(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 8-38°. There are three inequivalent V sites. In the first V site, V(1) is bonded to one O(2), two equivalent O(4), one F(4), and two equivalent F(2) atoms to form distorted VO3F3 octahedra that share corners with three equivalent Mg(1)F6 octahedra, corners with four equivalent V(3)O6 octahedra,  an edgeedge with one Mg(1)F6 octahedra, and edges with two equivalent V(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 8-53°. In the second V site, V(2) is bonded to one O(3), two equivalent O(1), one F(1), and two equivalent F(3) atoms to form distorted VO3F3 octahedra that share corners with two equivalent Mg(1)F6 octahedra, edges with two equivalent V(2)O3F3 octahedra, edges with two equivalent V(3)O6 octahedra, and  a faceface with one Mg(1)F6 octahedra. The corner-sharing octahedral tilt angles are 38°. In the third V site, V(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form VO6 octahedra that share corners with four equivalent V(1)O3F3 octahedra, edges with two equivalent V(2)O3F3 octahedra, and edges with two equivalent V(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one V(3) and two equivalent V(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one V(1) and two equivalent V(3) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one V(2) and two equivalent V(3) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one V(3) and two equivalent V(1) atoms. There are four inequivalent F sites. In the first F site, F(1) is bonded in an L-shaped geometry to one Mg(1) and one V(2) atom. In the second F site, F(2) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent V(1) atoms. In the third F site, F(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent V(2) atoms. In the fourth F site, F(4) is bonded in a bent 150 degrees geometry to one Mg(1) and one V(1) atom.
MgV3(OF)4 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one F(1), one F(4), two equivalent F(2), and two equivalent F(3) atoms to form MgF6 octahedra that share corners with two equivalent V(2)O3F3 octahedra, corners with three equivalent V(1)O3F3 octahedra,  an edgeedge with one V(1)O3F3 octahedra, edges with two equivalent Mg(1)F6 octahedra, and  a faceface with one V(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 8-38°. The Mg(1)-F(1) bond length is 1.96 Å. The Mg(1)-F(4) bond length is 1.91 Å. Both Mg(1)-F(2) bond lengths are 2.07 Å. Both Mg(1)-F(3) bond lengths are 2.18 Å. There are three inequivalent V sites. In the first V site, V(1) is bonded to one O(2), two equivalent O(4), one F(4), and two equivalent F(2) atoms to form distorted VO3F3 octahedra that share corners with three equivalent Mg(1)F6 octahedra, corners with four equivalent V(3)O6 octahedra,  an edgeedge with one Mg(1)F6 octahedra, and edges with two equivalent V(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 8-53°. The V(1)-O(2) bond length is 1.90 Å. Both V(1)-O(4) bond lengths are 1.93 Å. The V(1)-F(4) bond length is 1.97 Å. Both V(1)-F(2) bond lengths are 2.38 Å. In the second V site, V(2) is bonded to one O(3), two equivalent O(1), one F(1), and two equivalent F(3) atoms to form distorted VO3F3 octahedra that share corners with two equivalent Mg(1)F6 octahedra, edges with two equivalent V(2)O3F3 octahedra, edges with two equivalent V(3)O6 octahedra, and  a faceface with one Mg(1)F6 octahedra. The corner-sharing octahedral tilt angles are 38°. The V(2)-O(3) bond length is 1.97 Å. Both V(2)-O(1) bond lengths are 1.93 Å. The V(2)-F(1) bond length is 1.96 Å. Both V(2)-F(3) bond lengths are 2.26 Å. In the third V site, V(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form VO6 octahedra that share corners with four equivalent V(1)O3F3 octahedra, edges with two equivalent V(2)O3F3 octahedra, and edges with two equivalent V(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. The V(3)-O(1) bond length is 1.99 Å. The V(3)-O(4) bond length is 1.94 Å. Both V(3)-O(2) bond lengths are 2.03 Å. Both V(3)-O(3) bond lengths are 1.98 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one V(3) and two equivalent V(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one V(1) and two equivalent V(3) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one V(2) and two equivalent V(3) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one V(3) and two equivalent V(1) atoms. There are four inequivalent F sites. In the first F site, F(1) is bonded in an L-shaped geometry to one Mg(1) and one V(2) atom. In the second F site, F(2) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent V(1) atoms. In the third F site, F(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent V(2) atoms. In the fourth F site, F(4) is bonded in a bent 150 degrees geometry to one Mg(1) and one V(1) atom.