MgV4O5F7 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one F(2), one F(4), one F(5), and one F(6) atom to form distorted MgO2F4 pentagonal pyramids that share corners with two equivalent V(3)O2F4 octahedra,  an edgeedge with one V(1)O2F4 octahedra, and edges with two equivalent V(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 58-66°. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(3), one O(4), one F(1), one F(3), one F(4), and one F(7) atom to form VO2F4 octahedra that share corners with four equivalent V(3)O2F4 octahedra and  an edgeedge with one Mg(1)O2F4 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 31-39°. In the second V site, V(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one F(2), one F(5), and one F(6) atom. In the third V site, V(3) is bonded to one O(1), one O(5), one F(1), one F(3), one F(4), and one F(7) atom to form VO2F4 octahedra that share corners with two equivalent V(4)O3F3 octahedra, corners with four equivalent V(1)O2F4 octahedra, and corners with two equivalent Mg(1)O2F4 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 24-40°. In the fourth V site, V(4) is bonded to one O(1), one O(2), one O(5), one F(2), one F(5), and one F(6) atom to form VO3F3 octahedra that share corners with two equivalent V(3)O2F4 octahedra and edges with two equivalent Mg(1)O2F4 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 24-40°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(3), and one V(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one V(2) and one V(4) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one V(1), and one V(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to 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(3) and one V(4) atom. There are seven inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Mg(1), one V(2), and one V(4) atom. In the third F site, F(3) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom. In the fourth F site, F(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(3) atom. In the fifth F site, F(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one V(4) atom. In the sixth F site, F(6) is bonded in a 3-coordinate geometry to one Mg(1), one V(2), and one V(4) atom. In the seventh F site, F(7) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom.
MgV4O5F7 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one F(2), one F(4), one F(5), and one F(6) atom to form distorted MgO2F4 pentagonal pyramids that share corners with two equivalent V(3)O2F4 octahedra,  an edgeedge with one V(1)O2F4 octahedra, and edges with two equivalent V(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 58-66°. The Mg(1)-O(1) bond length is 2.02 Å. The Mg(1)-O(3) bond length is 2.06 Å. The Mg(1)-F(2) bond length is 2.14 Å. The Mg(1)-F(4) bond length is 2.00 Å. The Mg(1)-F(5) bond length is 2.09 Å. The Mg(1)-F(6) bond length is 2.09 Å. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(3), one O(4), one F(1), one F(3), one F(4), and one F(7) atom to form VO2F4 octahedra that share corners with four equivalent V(3)O2F4 octahedra and  an edgeedge with one Mg(1)O2F4 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 31-39°. The V(1)-O(3) bond length is 1.89 Å. The V(1)-O(4) bond length is 1.75 Å. The V(1)-F(1) bond length is 2.02 Å. The V(1)-F(3) bond length is 1.95 Å. The V(1)-F(4) bond length is 2.15 Å. The V(1)-F(7) bond length is 1.99 Å. In the second V site, V(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one F(2), one F(5), and one F(6) atom. The V(2)-O(2) bond length is 1.68 Å. The V(2)-O(3) bond length is 1.91 Å. The V(2)-O(4) bond length is 1.93 Å. The V(2)-F(2) bond length is 2.01 Å. The V(2)-F(5) bond length is 2.06 Å. The V(2)-F(6) bond length is 2.41 Å. In the third V site, V(3) is bonded to one O(1), one O(5), one F(1), one F(3), one F(4), and one F(7) atom to form VO2F4 octahedra that share corners with two equivalent V(4)O3F3 octahedra, corners with four equivalent V(1)O2F4 octahedra, and corners with two equivalent Mg(1)O2F4 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 24-40°. The V(3)-O(1) bond length is 1.94 Å. The V(3)-O(5) bond length is 1.93 Å. The V(3)-F(1) bond length is 2.00 Å. The V(3)-F(3) bond length is 2.04 Å. The V(3)-F(4) bond length is 2.08 Å. The V(3)-F(7) bond length is 2.00 Å. In the fourth V site, V(4) is bonded to one O(1), one O(2), one O(5), one F(2), one F(5), and one F(6) atom to form VO3F3 octahedra that share corners with two equivalent V(3)O2F4 octahedra and edges with two equivalent Mg(1)O2F4 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 24-40°. The V(4)-O(1) bond length is 1.90 Å. The V(4)-O(2) bond length is 2.02 Å. The V(4)-O(5) bond length is 1.72 Å. The V(4)-F(2) bond length is 2.08 Å. The V(4)-F(5) bond length is 2.06 Å. The V(4)-F(6) bond length is 1.98 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(3), and one V(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one V(2) and one V(4) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one V(1), and one V(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to 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(3) and one V(4) atom. There are seven inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Mg(1), one V(2), and one V(4) atom. In the third F site, F(3) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom. In the fourth F site, F(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(3) atom. In the fifth F site, F(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one V(4) atom. In the sixth F site, F(6) is bonded in a 3-coordinate geometry to one Mg(1), one V(2), and one V(4) atom. In the seventh F site, F(7) is bonded in a bent 150 degrees geometry to one V(1) and one V(3) atom.