Mg(SnO2)2 is Spinel-like structured and crystallizes in the monoclinic Cm space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(12), and two equivalent O(3) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(7)O6 octahedra, corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent Sn(8)O6 octahedra, corners with three equivalent Mg(5)O6 octahedra, and corners with four equivalent Sn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-69°. In the second Mg site, Mg(2) is bonded to one O(2), one O(4), and two equivalent O(8) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra, corners with two equivalent Sn(2)O6 octahedra, corners with two equivalent Sn(3)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra, and corners with four equivalent Sn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-69°. In the third Mg site, Mg(3) is bonded to one O(4), one O(9), two equivalent O(5), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with three equivalent Mg(2)O4 tetrahedra, corners with three equivalent Sn(6)O4 tetrahedra,  an edgeedge with one Sn(1)O6 octahedra,  an edgeedge with one Sn(3)O6 octahedra, edges with two equivalent Sn(2)O6 octahedra, and edges with two equivalent Sn(4)O6 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(6), and two equivalent O(14) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(3)O6 octahedra, corners with two equivalent Sn(4)O6 octahedra, corners with two equivalent Sn(7)O6 octahedra, corners with three equivalent Sn(5)O6 octahedra, and corners with four equivalent Sn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-64°. In the fifth Mg site, Mg(5) is bonded to one O(1), one O(18), two equivalent O(16), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Sn(9)O4 tetrahedra,  an edgeedge with one Sn(1)O6 octahedra,  an edgeedge with one Sn(7)O6 octahedra, edges with two equivalent Sn(2)O6 octahedra, and edges with two equivalent Sn(8)O6 octahedra. In the sixth Mg site, Mg(6) is bonded to one O(15), one O(17), and two equivalent O(11) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(7)O6 octahedra, corners with two equivalent Sn(3)O6 octahedra, corners with two equivalent Sn(8)O6 octahedra, corners with three equivalent Sn(5)O6 octahedra, and corners with four equivalent Sn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-63°. There are nine inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one O(2), one O(7), two equivalent O(3), and two equivalent O(5) atoms to form SnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Sn(9)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Sn(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, and edges with four equivalent Sn(2)O6 octahedra. In the second Sn site, Sn(2) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(9) atom to form SnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Sn(9)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Sn(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Sn(1)O6 octahedra, and edges with two equivalent Sn(2)O6 octahedra. In the third Sn site, Sn(3) is bonded to one O(13), one O(6), two equivalent O(11), and two equivalent O(8) atoms to form distorted SnO6 octahedra that share  a cornercorner with one Mg(4)O4 tetrahedra,  a cornercorner with one Sn(6)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mg(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, and edges with four equivalent Sn(4)O6 octahedra. In the fourth Sn site, Sn(4) is bonded to one O(11), one O(13), one O(15), one O(4), one O(6), and one O(8) atom to form SnO6 octahedra that share  a cornercorner with one Mg(4)O4 tetrahedra,  a cornercorner with one Sn(6)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mg(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, edges with two equivalent Sn(3)O6 octahedra, and edges with two equivalent Sn(4)O6 octahedra. In the fifth Sn site, Sn(5) is bonded to one O(10), one O(15), two equivalent O(11), and two equivalent O(14) atoms to form SnO6 octahedra that share corners with three equivalent Mg(4)O4 tetrahedra, corners with three equivalent Mg(6)O4 tetrahedra,  an edgeedge with one Sn(3)O6 octahedra,  an edgeedge with one Sn(7)O6 octahedra, edges with two equivalent Sn(4)O6 octahedra, and edges with two equivalent Sn(8)O6 octahedra. In the sixth Sn site, Sn(6) is bonded to one O(13), one O(9), and two equivalent O(5) atoms to form SnO4 tetrahedra that share  a cornercorner with one Sn(3)O6 octahedra, corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent Sn(4)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra, and corners with four equivalent Sn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-71°. In the seventh Sn site, Sn(7) is bonded to one O(12), one O(17), two equivalent O(14), and two equivalent O(16) atoms to form SnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mg(6)O4 tetrahedra, corners with two equivalent Mg(4)O4 tetrahedra, corners with two equivalent Sn(9)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, and edges with four equivalent Sn(8)O6 octahedra. In the eighth Sn site, Sn(8) is bonded to one O(10), one O(12), one O(14), one O(16), one O(17), and one O(18) atom to form SnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mg(6)O4 tetrahedra, corners with two equivalent Mg(4)O4 tetrahedra, corners with two equivalent Sn(9)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, edges with two equivalent Sn(7)O6 octahedra, and edges with two equivalent Sn(8)O6 octahedra. In the ninth Sn site, Sn(9) is bonded to one O(18), one O(7), and two equivalent O(16) atoms to form SnO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra, corners with two equivalent Sn(2)O6 octahedra, corners with two equivalent Sn(7)O6 octahedra, corners with three equivalent Mg(5)O6 octahedra, and corners with four equivalent Sn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-73°. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(5), and two equivalent Sn(2) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Sn(1), and two equivalent Sn(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(5), one Sn(1), and one Sn(2) atom. In the fourth O site, O(4) is bonded to one Mg(2), one Mg(3), and two equivalent Sn(4) atoms to form distorted OMg2Sn2 trigonal pyramids that share  a cornercorner with one O(9)MgSn3 tetrahedra, corners with two equivalent O(5)MgSn3 tetrahedra, and corners with two equivalent O(13)Sn4 tetrahedra. In the fifth O site, O(5) is bonded to one Mg(3), one Sn(1), one Sn(2), and one Sn(6) atom to form distorted OMgSn3 tetrahedra that share  a cornercorner with one O(5)MgSn3 tetrahedra,  a cornercorner with one O(9)MgSn3 tetrahedra,  a cornercorner with one O(13)Sn4 tetrahedra,  a cornercorner with one O(4)Mg2Sn2 trigonal pyramid,  an edgeedge with one O(5)MgSn3 tetrahedra,  an edgeedge with one O(9)MgSn3 tetrahedra, and  an edgeedge with one O(7)Sn4 tetrahedra. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Sn(3), and two equivalent Sn(4) atoms. In the seventh O site, O(7) is bonded to one Sn(1), one Sn(9), and two equivalent Sn(2) atoms to form a mixture of distorted edge and corner-sharing OSn4 tetrahedra. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mg(3), one Sn(3), and one Sn(4) atom. In the ninth O site, O(9) is bonded to one Mg(3), one Sn(6), and two equivalent Sn(2) atoms to form distorted OMgSn3 tetrahedra that share  a cornercorner with one O(13)Sn4 tetrahedra, corners with two equivalent O(5)MgSn3 tetrahedra,  a cornercorner with one O(4)Mg2Sn2 trigonal pyramid,  an edgeedge with one O(7)Sn4 tetrahedra, and edges with two equivalent O(5)MgSn3 tetrahedra. In the tenth O site, O(10) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Sn(5), and two equivalent Sn(8) atoms. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Sn(3), one Sn(4), and one Sn(5) atom. In the twelfth O site, O(12) is bonded to one Mg(1), one Sn(7), and two equivalent Sn(8) atoms to form distorted corner-sharing OMgSn3 trigonal pyramids. In the thirteenth O site, O(13) is bonded to one Sn(3), one Sn(6), and two equivalent Sn(4) atoms to form OSn4 tetrahedra that share  a cornercorner with one O(9)MgSn3 tetrahedra, corners with two equivalent O(5)MgSn3 tetrahedra, and corners with two equivalent O(4)Mg2Sn2 trigonal pyramids. In the fourteenth O site, O(14) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Sn(5), one Sn(7), and one Sn(8) atom. In the fifteenth O site, O(15) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Sn(5), and two equivalent Sn(4) atoms. In the sixteenth O site, O(16) is bonded to one Mg(5), one Sn(7), one Sn(8), and one Sn(9) atom to form distorted OMgSn3 trigonal pyramids that share  a cornercorner with one O(18)MgSn3 tetrahedra,  a cornercorner with one O(7)Sn4 tetrahedra,  a cornercorner with one O(16)MgSn3 trigonal pyramid, corners with two equivalent O(12)MgSn3 trigonal pyramids,  an edgeedge with one O(18)MgSn3 tetrahedra, and  an edgeedge with one O(16)MgSn3 trigonal pyramid. In the seventeenth O site, O(17) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Sn(7), and two equivalent Sn(8) atoms. In the eighteenth O site, O(18) is bonded to one Mg(5), one Sn(9), and two equivalent Sn(8) atoms to form distorted OMgSn3 tetrahedra that share  a cornercorner with one O(7)Sn4 tetrahedra, corners with two equivalent O(12)MgSn3 trigonal pyramids, corners with two equivalent O(16)MgSn3 trigonal pyramids, and edges with two equivalent O(16)MgSn3 trigonal pyramids.
Mg(SnO2)2 is Spinel-like structured and crystallizes in the monoclinic Cm space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(12), and two equivalent O(3) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(7)O6 octahedra, corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent Sn(8)O6 octahedra, corners with three equivalent Mg(5)O6 octahedra, and corners with four equivalent Sn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-69°. The Mg(1)-O(1) bond length is 2.15 Å. The Mg(1)-O(12) bond length is 2.10 Å. Both Mg(1)-O(3) bond lengths are 2.15 Å. In the second Mg site, Mg(2) is bonded to one O(2), one O(4), and two equivalent O(8) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra, corners with two equivalent Sn(2)O6 octahedra, corners with two equivalent Sn(3)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra, and corners with four equivalent Sn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-69°. The Mg(2)-O(2) bond length is 2.09 Å. The Mg(2)-O(4) bond length is 2.45 Å. Both Mg(2)-O(8) bond lengths are 2.05 Å. In the third Mg site, Mg(3) is bonded to one O(4), one O(9), two equivalent O(5), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with three equivalent Mg(2)O4 tetrahedra, corners with three equivalent Sn(6)O4 tetrahedra,  an edgeedge with one Sn(1)O6 octahedra,  an edgeedge with one Sn(3)O6 octahedra, edges with two equivalent Sn(2)O6 octahedra, and edges with two equivalent Sn(4)O6 octahedra. The Mg(3)-O(4) bond length is 2.17 Å. The Mg(3)-O(9) bond length is 2.14 Å. Both Mg(3)-O(5) bond lengths are 2.19 Å. Both Mg(3)-O(8) bond lengths are 2.18 Å. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(6), and two equivalent O(14) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(3)O6 octahedra, corners with two equivalent Sn(4)O6 octahedra, corners with two equivalent Sn(7)O6 octahedra, corners with three equivalent Sn(5)O6 octahedra, and corners with four equivalent Sn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-64°. The Mg(4)-O(10) bond length is 2.24 Å. The Mg(4)-O(6) bond length is 2.09 Å. Both Mg(4)-O(14) bond lengths are 2.00 Å. In the fifth Mg site, Mg(5) is bonded to one O(1), one O(18), two equivalent O(16), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Sn(9)O4 tetrahedra,  an edgeedge with one Sn(1)O6 octahedra,  an edgeedge with one Sn(7)O6 octahedra, edges with two equivalent Sn(2)O6 octahedra, and edges with two equivalent Sn(8)O6 octahedra. The Mg(5)-O(1) bond length is 2.23 Å. The Mg(5)-O(18) bond length is 2.09 Å. Both Mg(5)-O(16) bond lengths are 2.10 Å. Both Mg(5)-O(3) bond lengths are 2.23 Å. In the sixth Mg site, Mg(6) is bonded to one O(15), one O(17), and two equivalent O(11) atoms to form MgO4 tetrahedra that share  a cornercorner with one Sn(7)O6 octahedra, corners with two equivalent Sn(3)O6 octahedra, corners with two equivalent Sn(8)O6 octahedra, corners with three equivalent Sn(5)O6 octahedra, and corners with four equivalent Sn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-63°. The Mg(6)-O(15) bond length is 2.21 Å. The Mg(6)-O(17) bond length is 2.10 Å. Both Mg(6)-O(11) bond lengths are 2.02 Å. There are nine inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one O(2), one O(7), two equivalent O(3), and two equivalent O(5) atoms to form SnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Sn(9)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Sn(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, and edges with four equivalent Sn(2)O6 octahedra. The Sn(1)-O(2) bond length is 2.17 Å. The Sn(1)-O(7) bond length is 2.26 Å. Both Sn(1)-O(3) bond lengths are 2.14 Å. Both Sn(1)-O(5) bond lengths are 2.13 Å. In the second Sn site, Sn(2) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(9) atom to form SnO6 octahedra that share  a cornercorner with one Mg(2)O4 tetrahedra,  a cornercorner with one Sn(9)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Sn(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Sn(1)O6 octahedra, and edges with two equivalent Sn(2)O6 octahedra. The Sn(2)-O(1) bond length is 2.28 Å. The Sn(2)-O(2) bond length is 2.38 Å. The Sn(2)-O(3) bond length is 2.33 Å. The Sn(2)-O(5) bond length is 2.20 Å. The Sn(2)-O(7) bond length is 2.22 Å. The Sn(2)-O(9) bond length is 2.15 Å. In the third Sn site, Sn(3) is bonded to one O(13), one O(6), two equivalent O(11), and two equivalent O(8) atoms to form distorted SnO6 octahedra that share  a cornercorner with one Mg(4)O4 tetrahedra,  a cornercorner with one Sn(6)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mg(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, and edges with four equivalent Sn(4)O6 octahedra. The Sn(3)-O(13) bond length is 2.28 Å. The Sn(3)-O(6) bond length is 2.60 Å. Both Sn(3)-O(11) bond lengths are 2.34 Å. Both Sn(3)-O(8) bond lengths are 2.54 Å. In the fourth Sn site, Sn(4) is bonded to one O(11), one O(13), one O(15), one O(4), one O(6), and one O(8) atom to form SnO6 octahedra that share  a cornercorner with one Mg(4)O4 tetrahedra,  a cornercorner with one Sn(6)O4 tetrahedra, corners with two equivalent Mg(2)O4 tetrahedra, corners with two equivalent Mg(6)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, edges with two equivalent Sn(3)O6 octahedra, and edges with two equivalent Sn(4)O6 octahedra. The Sn(4)-O(11) bond length is 2.12 Å. The Sn(4)-O(13) bond length is 2.13 Å. The Sn(4)-O(15) bond length is 2.25 Å. The Sn(4)-O(4) bond length is 2.17 Å. The Sn(4)-O(6) bond length is 2.18 Å. The Sn(4)-O(8) bond length is 2.10 Å. In the fifth Sn site, Sn(5) is bonded to one O(10), one O(15), two equivalent O(11), and two equivalent O(14) atoms to form SnO6 octahedra that share corners with three equivalent Mg(4)O4 tetrahedra, corners with three equivalent Mg(6)O4 tetrahedra,  an edgeedge with one Sn(3)O6 octahedra,  an edgeedge with one Sn(7)O6 octahedra, edges with two equivalent Sn(4)O6 octahedra, and edges with two equivalent Sn(8)O6 octahedra. The Sn(5)-O(10) bond length is 2.59 Å. The Sn(5)-O(15) bond length is 2.48 Å. Both Sn(5)-O(11) bond lengths are 2.46 Å. Both Sn(5)-O(14) bond lengths are 2.40 Å. In the sixth Sn site, Sn(6) is bonded to one O(13), one O(9), and two equivalent O(5) atoms to form SnO4 tetrahedra that share  a cornercorner with one Sn(3)O6 octahedra, corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent Sn(4)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra, and corners with four equivalent Sn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-71°. The Sn(6)-O(13) bond length is 2.39 Å. The Sn(6)-O(9) bond length is 2.44 Å. Both Sn(6)-O(5) bond lengths are 2.30 Å. In the seventh Sn site, Sn(7) is bonded to one O(12), one O(17), two equivalent O(14), and two equivalent O(16) atoms to form SnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mg(6)O4 tetrahedra, corners with two equivalent Mg(4)O4 tetrahedra, corners with two equivalent Sn(9)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, and edges with four equivalent Sn(8)O6 octahedra. The Sn(7)-O(12) bond length is 2.50 Å. The Sn(7)-O(17) bond length is 2.46 Å. Both Sn(7)-O(14) bond lengths are 2.47 Å. Both Sn(7)-O(16) bond lengths are 2.39 Å. In the eighth Sn site, Sn(8) is bonded to one O(10), one O(12), one O(14), one O(16), one O(17), and one O(18) atom to form SnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mg(6)O4 tetrahedra, corners with two equivalent Mg(4)O4 tetrahedra, corners with two equivalent Sn(9)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Sn(5)O6 octahedra, edges with two equivalent Sn(7)O6 octahedra, and edges with two equivalent Sn(8)O6 octahedra. The Sn(8)-O(10) bond length is 2.21 Å. The Sn(8)-O(12) bond length is 2.18 Å. The Sn(8)-O(14) bond length is 2.07 Å. The Sn(8)-O(16) bond length is 2.08 Å. The Sn(8)-O(17) bond length is 2.23 Å. The Sn(8)-O(18) bond length is 2.09 Å. In the ninth Sn site, Sn(9) is bonded to one O(18), one O(7), and two equivalent O(16) atoms to form SnO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra, corners with two equivalent Sn(2)O6 octahedra, corners with two equivalent Sn(7)O6 octahedra, corners with three equivalent Mg(5)O6 octahedra, and corners with four equivalent Sn(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-73°. The Sn(9)-O(18) bond length is 2.50 Å. The Sn(9)-O(7) bond length is 2.35 Å. Both Sn(9)-O(16) bond lengths are 2.21 Å. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(5), and two equivalent Sn(2) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Sn(1), and two equivalent Sn(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(5), one Sn(1), and one Sn(2) atom. In the fourth O site, O(4) is bonded to one Mg(2), one Mg(3), and two equivalent Sn(4) atoms to form distorted OMg2Sn2 trigonal pyramids that share  a cornercorner with one O(9)MgSn3 tetrahedra, corners with two equivalent O(5)MgSn3 tetrahedra, and corners with two equivalent O(13)Sn4 tetrahedra. In the fifth O site, O(5) is bonded to one Mg(3), one Sn(1), one Sn(2), and one Sn(6) atom to form distorted OMgSn3 tetrahedra that share  a cornercorner with one O(5)MgSn3 tetrahedra,  a cornercorner with one O(9)MgSn3 tetrahedra,  a cornercorner with one O(13)Sn4 tetrahedra,  a cornercorner with one O(4)Mg2Sn2 trigonal pyramid,  an edgeedge with one O(5)MgSn3 tetrahedra,  an edgeedge with one O(9)MgSn3 tetrahedra, and  an edgeedge with one O(7)Sn4 tetrahedra. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Sn(3), and two equivalent Sn(4) atoms. In the seventh O site, O(7) is bonded to one Sn(1), one Sn(9), and two equivalent Sn(2) atoms to form a mixture of distorted edge and corner-sharing OSn4 tetrahedra. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mg(3), one Sn(3), and one Sn(4) atom. In the ninth O site, O(9) is bonded to one Mg(3), one Sn(6), and two equivalent Sn(2) atoms to form distorted OMgSn3 tetrahedra that share  a cornercorner with one O(13)Sn4 tetrahedra, corners with two equivalent O(5)MgSn3 tetrahedra,  a cornercorner with one O(4)Mg2Sn2 trigonal pyramid,  an edgeedge with one O(7)Sn4 tetrahedra, and edges with two equivalent O(5)MgSn3 tetrahedra. In the tenth O site, O(10) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Sn(5), and two equivalent Sn(8) atoms. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Sn(3), one Sn(4), and one Sn(5) atom. In the twelfth O site, O(12) is bonded to one Mg(1), one Sn(7), and two equivalent Sn(8) atoms to form distorted corner-sharing OMgSn3 trigonal pyramids. In the thirteenth O site, O(13) is bonded to one Sn(3), one Sn(6), and two equivalent Sn(4) atoms to form OSn4 tetrahedra that share  a cornercorner with one O(9)MgSn3 tetrahedra, corners with two equivalent O(5)MgSn3 tetrahedra, and corners with two equivalent O(4)Mg2Sn2 trigonal pyramids. In the fourteenth O site, O(14) is bonded in a distorted rectangular see-saw-like geometry to one Mg(4), one Sn(5), one Sn(7), and one Sn(8) atom. In the fifteenth O site, O(15) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Sn(5), and two equivalent Sn(4) atoms. In the sixteenth O site, O(16) is bonded to one Mg(5), one Sn(7), one Sn(8), and one Sn(9) atom to form distorted OMgSn3 trigonal pyramids that share  a cornercorner with one O(18)MgSn3 tetrahedra,  a cornercorner with one O(7)Sn4 tetrahedra,  a cornercorner with one O(16)MgSn3 trigonal pyramid, corners with two equivalent O(12)MgSn3 trigonal pyramids,  an edgeedge with one O(18)MgSn3 tetrahedra, and  an edgeedge with one O(16)MgSn3 trigonal pyramid. In the seventeenth O site, O(17) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Sn(7), and two equivalent Sn(8) atoms. In the eighteenth O site, O(18) is bonded to one Mg(5), one Sn(9), and two equivalent Sn(8) atoms to form distorted OMgSn3 tetrahedra that share  a cornercorner with one O(7)Sn4 tetrahedra, corners with two equivalent O(12)MgSn3 trigonal pyramids, corners with two equivalent O(16)MgSn3 trigonal pyramids, and edges with two equivalent O(16)MgSn3 trigonal pyramids.