Mg(IO3)2 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded to one O(3), one O(5), one O(6), and two equivalent O(1) atoms to form edge-sharing MgO5 square pyramids. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one I(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one I(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one I(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one I(1) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Mg(1) and one I(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one I(2) atom. There are two inequivalent I sites. In the first I site, I(1) is bonded in a 3-coordinate geometry to one O(1), one O(3), and one O(4) atom. In the second I site, I(2) is bonded in a 3-coordinate geometry to one O(2), one O(5), and one O(6) atom.
Mg(IO3)2 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded to one O(3), one O(5), one O(6), and two equivalent O(1) atoms to form edge-sharing MgO5 square pyramids. The Mg(1)-O(3) bond length is 2.02 Å. The Mg(1)-O(5) bond length is 2.10 Å. The Mg(1)-O(6) bond length is 2.11 Å. There is one shorter (2.07 Å) and one longer (2.10 Å) Mg(1)-O(1) bond length. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one I(1) atom. The O(1)-I(1) bond length is 1.87 Å. In the second O site, O(2) is bonded in a single-bond geometry to one I(2) atom. The O(2)-I(2) bond length is 1.84 Å. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one I(1) atom. The O(3)-I(1) bond length is 1.80 Å. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one I(1) atom. The O(4)-I(1) bond length is 1.83 Å. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Mg(1) and one I(2) atom. The O(5)-I(2) bond length is 1.84 Å. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one I(2) atom. The O(6)-I(2) bond length is 1.85 Å. There are two inequivalent I sites. In the first I site, I(1) is bonded in a 3-coordinate geometry to one O(1), one O(3), and one O(4) atom. In the second I site, I(2) is bonded in a 3-coordinate geometry to one O(2), one O(5), and one O(6) atom.