MgNb4(O2F)4 crystallizes in the monoclinic P2 space group. Mg(1) is bonded in a distorted trigonal planar geometry to one O(6) and two equivalent O(1) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(5), one O(6), one F(1), and one F(2) atom to form corner-sharing NbO4F2 octahedra. The corner-sharing octahedral tilt angles range from 17-42°. In the second Nb site, Nb(2) is bonded to one O(1), one O(3), one O(4), one O(5), one F(1), and one F(2) atom to form corner-sharing NbO4F2 octahedra. The corner-sharing octahedral tilt angles range from 15-42°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Nb(2) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Nb(1) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(2) atom. In the second F site, F(2) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(2) atom.
MgNb4(O2F)4 crystallizes in the monoclinic P2 space group. Mg(1) is bonded in a distorted trigonal planar geometry to one O(6) and two equivalent O(1) atoms. The Mg(1)-O(6) bond length is 1.99 Å. Both Mg(1)-O(1) bond lengths are 2.01 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(5), one O(6), one F(1), and one F(2) atom to form corner-sharing NbO4F2 octahedra. The corner-sharing octahedral tilt angles range from 17-42°. The Nb(1)-O(1) bond length is 1.99 Å. The Nb(1)-O(2) bond length is 1.93 Å. The Nb(1)-O(5) bond length is 2.07 Å. The Nb(1)-O(6) bond length is 2.05 Å. The Nb(1)-F(1) bond length is 2.07 Å. The Nb(1)-F(2) bond length is 2.06 Å. In the second Nb site, Nb(2) is bonded to one O(1), one O(3), one O(4), one O(5), one F(1), and one F(2) atom to form corner-sharing NbO4F2 octahedra. The corner-sharing octahedral tilt angles range from 15-42°. The Nb(2)-O(1) bond length is 2.23 Å. The Nb(2)-O(3) bond length is 1.98 Å. The Nb(2)-O(4) bond length is 1.95 Å. The Nb(2)-O(5) bond length is 1.91 Å. The Nb(2)-F(1) bond length is 2.07 Å. The Nb(2)-F(2) bond length is 2.06 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Nb(2) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Nb(1) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(2) atom. In the second F site, F(2) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(2) atom.