Na3MgMn2SbO6 crystallizes in the monoclinic Cm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(3), one O(4), and two equivalent O(1) atoms. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form MgO4 tetrahedra that share corners with four equivalent Mn(1)O4 tetrahedra. Mn(1) is bonded to one O(1), one O(2), and two equivalent O(4) atoms to form distorted MnO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra and corners with three equivalent Mn(1)O4 tetrahedra. Sb(1) is bonded in a trigonal non-coplanar geometry to one O(3) and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Mg(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(1), one Mg(1), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Mg(1), and one Sb(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), two equivalent Mn(1), and one Sb(1) atom.
Na3MgMn2SbO6 crystallizes in the monoclinic Cm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. The Na(1)-O(2) bond length is 2.81 Å. The Na(1)-O(3) bond length is 2.27 Å. Both Na(1)-O(1) bond lengths are 2.48 Å. Both Na(1)-O(4) bond lengths are 2.72 Å. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(3), one O(4), and two equivalent O(1) atoms. The Na(2)-O(3) bond length is 2.79 Å. The Na(2)-O(4) bond length is 2.48 Å. There is one shorter (2.17 Å) and one longer (2.33 Å) Na(2)-O(1) bond length. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form MgO4 tetrahedra that share corners with four equivalent Mn(1)O4 tetrahedra. The Mg(1)-O(2) bond length is 1.98 Å. The Mg(1)-O(3) bond length is 2.02 Å. Both Mg(1)-O(1) bond lengths are 1.92 Å. Mn(1) is bonded to one O(1), one O(2), and two equivalent O(4) atoms to form distorted MnO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra and corners with three equivalent Mn(1)O4 tetrahedra. The Mn(1)-O(1) bond length is 1.99 Å. The Mn(1)-O(2) bond length is 2.08 Å. There is one shorter (2.22 Å) and one longer (2.33 Å) Mn(1)-O(4) bond length. Sb(1) is bonded in a trigonal non-coplanar geometry to one O(3) and two equivalent O(4) atoms. The Sb(1)-O(3) bond length is 1.99 Å. Both Sb(1)-O(4) bond lengths are 2.07 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Mg(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(1), one Mg(1), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Mg(1), and one Sb(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), two equivalent Mn(1), and one Sb(1) atom.