MgV4O10 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent V(2)O4 tetrahedra and edges with four equivalent V(1)O6 octahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form VO6 octahedra that share corners with four equivalent V(2)O4 tetrahedra,  an edgeedge with one V(1)O6 octahedra, and edges with two equivalent Mg(1)O6 octahedra. In the second V site, V(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form VO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra and corners with four equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-64°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent V(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one V(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one V(1) and one V(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one V(1) and one V(2) atom.
MgV4O10 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent V(2)O4 tetrahedra and edges with four equivalent V(1)O6 octahedra. Both Mg(1)-O(1) bond lengths are 2.05 Å. Both Mg(1)-O(2) bond lengths are 2.18 Å. Both Mg(1)-O(4) bond lengths are 2.09 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form VO6 octahedra that share corners with four equivalent V(2)O4 tetrahedra,  an edgeedge with one V(1)O6 octahedra, and edges with two equivalent Mg(1)O6 octahedra. The V(1)-O(2) bond length is 2.07 Å. The V(1)-O(3) bond length is 1.91 Å. The V(1)-O(4) bond length is 2.01 Å. The V(1)-O(5) bond length is 1.99 Å. There is one shorter (1.77 Å) and one longer (2.10 Å) V(1)-O(1) bond length. In the second V site, V(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form VO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra and corners with four equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-64°. The V(2)-O(2) bond length is 1.75 Å. The V(2)-O(3) bond length is 1.74 Å. The V(2)-O(4) bond length is 1.79 Å. The V(2)-O(5) bond length is 1.71 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent V(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one V(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one V(1) and one V(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one V(1) and one V(2) atom.