Mg14CuSnO16 is alpha Po-derived structured and crystallizes in the orthorhombic Pmmm space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1), two equivalent O(6), and two equivalent O(9) atoms to form MgO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, edges with four equivalent Mg(4)O6 octahedra, edges with four equivalent Mg(5)O6 octahedra, and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. In the second Mg site, Mg(2) is bonded to two equivalent O(2), two equivalent O(7), and two equivalent O(9) atoms to form MgO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra; corners with two equivalent Mg(2)O6 octahedra; corners with two equivalent Sn(1)O6 octahedra; edges with four equivalent Mg(4)O6 octahedra; edges with four Mg(6,6)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. In the third Mg site, Mg(3) is bonded to one O(4), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with two equivalent Mg(4)O6 octahedra; corners with four equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(5)O6 octahedra; edges with two Mg(6,6)O6 octahedra; edges with two equivalent Cu(1)O6 octahedra; edges with two equivalent Sn(1)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the fourth Mg site, Mg(4) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(9) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the fifth Mg site, Mg(5) is bonded to one O(4), one O(6), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(6)O6 octahedra, corners with four equivalent Mg(5)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the sixth Mg site, Mg(6) is bonded to one O(5), one O(7), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra; corners with four Mg(6,6)O6 octahedra; edges with two equivalent Mg(2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(4)O6 octahedra; edges with two equivalent Sn(1)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the seventh Mg site, Mg(6) is bonded to one O(5), one O(7), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra; corners with four Mg(6,6)O6 octahedra; edges with two equivalent Mg(2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(4)O6 octahedra; edges with two equivalent Sn(1)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the eighth Mg site, Mg(7) is bonded to one O(1), one O(2), one O(8), one O(9), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Mg(7)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Cu(1)O6 octahedra,  an edgeedge with one Sn(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Mg(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-7°. Cu(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(8) atoms to form CuO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, corners with two equivalent Sn(1)O6 octahedra, edges with four equivalent Mg(3)O6 octahedra, edges with four equivalent Mg(5)O6 octahedra, and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. Sn(1) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form SnO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra; corners with two equivalent Cu(1)O6 octahedra; corners with two equivalent Sn(1)O6 octahedra; edges with four equivalent Mg(3)O6 octahedra; edges with four Mg(6,6)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Mg(5), two equivalent Mg(7), and one Cu(1) atom to form OMg5Cu octahedra that share corners with two equivalent O(2)Mg5Sn octahedra, corners with four equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(4)Mg4Cu2 octahedra, edges with two equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(6)Mg6 octahedra, edges with two equivalent O(9)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second O site, O(2) is bonded to one Mg(2), two equivalent Mg(6), two equivalent Mg(7), and one Sn(1) atom to form OMg5Sn octahedra that share corners with two equivalent O(1)Mg5Cu octahedra, corners with four equivalent O(2)Mg5Sn octahedra, edges with two equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(5)Mg4Sn2 octahedra, edges with two equivalent O(7)Mg6 octahedra, edges with two equivalent O(9)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third O site, O(3) is bonded to one Mg(3), one Mg(4), one Mg(5), one Mg(6), and two equivalent Mg(7) atoms to form OMg6 octahedra that share corners with six equivalent O(3)Mg6 octahedra,  an edgeedge with one O(4)Mg4Cu2 octahedra,  an edgeedge with one O(5)Mg4Sn2 octahedra,  an edgeedge with one O(6)Mg6 octahedra,  an edgeedge with one O(7)Mg6 octahedra, edges with two equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(2)Mg5Sn octahedra, and edges with two equivalent O(9)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the fourth O site, O(4) is bonded to two equivalent Mg(3), two equivalent Mg(5), and two equivalent Cu(1) atoms to form OMg4Cu2 octahedra that share corners with two equivalent O(4)Mg4Cu2 octahedra, corners with two equivalent O(5)Mg4Sn2 octahedra, corners with two equivalent O(6)Mg6 octahedra, edges with four equivalent O(8)Mg4CuSn octahedra, edges with four equivalent O(1)Mg5Cu octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded to two equivalent Mg(3); two Mg(6,6); and two equivalent Sn(1) atoms to form OMg4Sn2 octahedra that share corners with two equivalent O(4)Mg4Cu2 octahedra, corners with two equivalent O(5)Mg4Sn2 octahedra, corners with two equivalent O(7)Mg6 octahedra, edges with four equivalent O(8)Mg4CuSn octahedra, edges with four equivalent O(2)Mg5Sn octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the sixth O site, O(6) is bonded to two equivalent Mg(1), two equivalent Mg(4), and two equivalent Mg(5) atoms to form OMg6 octahedra that share corners with two equivalent O(4)Mg4Cu2 octahedra, corners with two equivalent O(6)Mg6 octahedra, corners with two equivalent O(7)Mg6 octahedra, edges with four equivalent O(1)Mg5Cu octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with four equivalent O(9)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the seventh O site, O(7) is bonded to two equivalent Mg(2); two equivalent Mg(4); and two Mg(6,6) atoms to form OMg6 octahedra that share corners with two equivalent O(5)Mg4Sn2 octahedra, corners with two equivalent O(6)Mg6 octahedra, corners with two equivalent O(7)Mg6 octahedra, edges with four equivalent O(2)Mg5Sn octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with four equivalent O(9)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the eighth O site, O(8) is bonded to two equivalent Mg(3), two equivalent Mg(7), one Cu(1), and one Sn(1) atom to form OMg4CuSn octahedra that share corners with two equivalent O(9)Mg6 octahedra, corners with four equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(4)Mg4Cu2 octahedra, edges with two equivalent O(5)Mg4Sn2 octahedra, edges with two equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(2)Mg5Sn octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the ninth O site, O(9) is bonded to one Mg(1), one Mg(2), two equivalent Mg(4), and two equivalent Mg(7) atoms to form OMg6 octahedra that share corners with two equivalent O(8)Mg4CuSn octahedra, corners with four equivalent O(9)Mg6 octahedra, edges with two equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(2)Mg5Sn octahedra, edges with two equivalent O(6)Mg6 octahedra, edges with two equivalent O(7)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°.
Mg14CuSnO16 is alpha Po-derived structured and crystallizes in the orthorhombic Pmmm space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1), two equivalent O(6), and two equivalent O(9) atoms to form MgO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, edges with four equivalent Mg(4)O6 octahedra, edges with four equivalent Mg(5)O6 octahedra, and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. Both Mg(1)-O(1) bond lengths are 2.02 Å. Both Mg(1)-O(6) bond lengths are 2.15 Å. Both Mg(1)-O(9) bond lengths are 2.18 Å. In the second Mg site, Mg(2) is bonded to two equivalent O(2), two equivalent O(7), and two equivalent O(9) atoms to form MgO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra; corners with two equivalent Mg(2)O6 octahedra; corners with two equivalent Sn(1)O6 octahedra; edges with four equivalent Mg(4)O6 octahedra; edges with four Mg(6,6)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. Both Mg(2)-O(2) bond lengths are 2.07 Å. Both Mg(2)-O(7) bond lengths are 2.15 Å. Both Mg(2)-O(9) bond lengths are 2.14 Å. In the third Mg site, Mg(3) is bonded to one O(4), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with two equivalent Mg(4)O6 octahedra; corners with four equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(5)O6 octahedra; edges with two Mg(6,6)O6 octahedra; edges with two equivalent Cu(1)O6 octahedra; edges with two equivalent Sn(1)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. The Mg(3)-O(4) bond length is 2.02 Å. The Mg(3)-O(5) bond length is 2.29 Å. Both Mg(3)-O(3) bond lengths are 2.17 Å. Both Mg(3)-O(8) bond lengths are 2.16 Å. In the fourth Mg site, Mg(4) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(9) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. The Mg(4)-O(6) bond length is 2.13 Å. The Mg(4)-O(7) bond length is 2.19 Å. Both Mg(4)-O(3) bond lengths are 2.20 Å. Both Mg(4)-O(9) bond lengths are 2.15 Å. In the fifth Mg site, Mg(5) is bonded to one O(4), one O(6), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(6)O6 octahedra, corners with four equivalent Mg(5)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Cu(1)O6 octahedra, and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. The Mg(5)-O(4) bond length is 2.17 Å. The Mg(5)-O(6) bond length is 2.19 Å. Both Mg(5)-O(1) bond lengths are 2.16 Å. Both Mg(5)-O(3) bond lengths are 2.17 Å. In the sixth Mg site, Mg(6) is bonded to one O(5), one O(7), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra; corners with four Mg(6,6)O6 octahedra; edges with two equivalent Mg(2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(4)O6 octahedra; edges with two equivalent Sn(1)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. The Mg(6)-O(5) bond length is 2.28 Å. The Mg(6)-O(7) bond length is 2.09 Å. Both Mg(6)-O(2) bond lengths are 2.15 Å. Both Mg(6)-O(3) bond lengths are 2.15 Å. In the seventh Mg site, Mg(6) is bonded to one O(5), one O(7), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra; corners with four Mg(6,6)O6 octahedra; edges with two equivalent Mg(2)O6 octahedra; edges with two equivalent Mg(3)O6 octahedra; edges with two equivalent Mg(4)O6 octahedra; edges with two equivalent Sn(1)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. The Mg(6)-O(5) bond length is 2.28 Å. The Mg(6)-O(7) bond length is 2.09 Å. Both Mg(6)-O(2) bond lengths are 2.15 Å. Both Mg(6)-O(3) bond lengths are 2.15 Å. In the eighth Mg site, Mg(7) is bonded to one O(1), one O(2), one O(8), one O(9), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Mg(7)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Cu(1)O6 octahedra,  an edgeedge with one Sn(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Mg(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-7°. The Mg(7)-O(1) bond length is 2.08 Å. The Mg(7)-O(2) bond length is 2.24 Å. The Mg(7)-O(8) bond length is 2.22 Å. The Mg(7)-O(9) bond length is 2.15 Å. Both Mg(7)-O(3) bond lengths are 2.16 Å. Cu(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(8) atoms to form CuO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, corners with two equivalent Sn(1)O6 octahedra, edges with four equivalent Mg(3)O6 octahedra, edges with four equivalent Mg(5)O6 octahedra, and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. Both Cu(1)-O(1) bond lengths are 2.34 Å. Both Cu(1)-O(4) bond lengths are 2.15 Å. Both Cu(1)-O(8) bond lengths are 2.12 Å. Sn(1) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form SnO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra; corners with two equivalent Cu(1)O6 octahedra; corners with two equivalent Sn(1)O6 octahedra; edges with four equivalent Mg(3)O6 octahedra; edges with four Mg(6,6)O6 octahedra; and edges with four equivalent Mg(7)O6 octahedra. The corner-sharing octahedra are not tilted. Both Sn(1)-O(2) bond lengths are 2.30 Å. Both Sn(1)-O(5) bond lengths are 2.15 Å. Both Sn(1)-O(8) bond lengths are 2.20 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Mg(5), two equivalent Mg(7), and one Cu(1) atom to form OMg5Cu octahedra that share corners with two equivalent O(2)Mg5Sn octahedra, corners with four equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(4)Mg4Cu2 octahedra, edges with two equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(6)Mg6 octahedra, edges with two equivalent O(9)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second O site, O(2) is bonded to one Mg(2), two equivalent Mg(6), two equivalent Mg(7), and one Sn(1) atom to form OMg5Sn octahedra that share corners with two equivalent O(1)Mg5Cu octahedra, corners with four equivalent O(2)Mg5Sn octahedra, edges with two equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(5)Mg4Sn2 octahedra, edges with two equivalent O(7)Mg6 octahedra, edges with two equivalent O(9)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third O site, O(3) is bonded to one Mg(3), one Mg(4), one Mg(5), one Mg(6), and two equivalent Mg(7) atoms to form OMg6 octahedra that share corners with six equivalent O(3)Mg6 octahedra,  an edgeedge with one O(4)Mg4Cu2 octahedra,  an edgeedge with one O(5)Mg4Sn2 octahedra,  an edgeedge with one O(6)Mg6 octahedra,  an edgeedge with one O(7)Mg6 octahedra, edges with two equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(2)Mg5Sn octahedra, and edges with two equivalent O(9)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the fourth O site, O(4) is bonded to two equivalent Mg(3), two equivalent Mg(5), and two equivalent Cu(1) atoms to form OMg4Cu2 octahedra that share corners with two equivalent O(4)Mg4Cu2 octahedra, corners with two equivalent O(5)Mg4Sn2 octahedra, corners with two equivalent O(6)Mg6 octahedra, edges with four equivalent O(8)Mg4CuSn octahedra, edges with four equivalent O(1)Mg5Cu octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded to two equivalent Mg(3); two Mg(6,6); and two equivalent Sn(1) atoms to form OMg4Sn2 octahedra that share corners with two equivalent O(4)Mg4Cu2 octahedra, corners with two equivalent O(5)Mg4Sn2 octahedra, corners with two equivalent O(7)Mg6 octahedra, edges with four equivalent O(8)Mg4CuSn octahedra, edges with four equivalent O(2)Mg5Sn octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the sixth O site, O(6) is bonded to two equivalent Mg(1), two equivalent Mg(4), and two equivalent Mg(5) atoms to form OMg6 octahedra that share corners with two equivalent O(4)Mg4Cu2 octahedra, corners with two equivalent O(6)Mg6 octahedra, corners with two equivalent O(7)Mg6 octahedra, edges with four equivalent O(1)Mg5Cu octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with four equivalent O(9)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the seventh O site, O(7) is bonded to two equivalent Mg(2); two equivalent Mg(4); and two Mg(6,6) atoms to form OMg6 octahedra that share corners with two equivalent O(5)Mg4Sn2 octahedra, corners with two equivalent O(6)Mg6 octahedra, corners with two equivalent O(7)Mg6 octahedra, edges with four equivalent O(2)Mg5Sn octahedra, edges with four equivalent O(3)Mg6 octahedra, and edges with four equivalent O(9)Mg6 octahedra. The corner-sharing octahedra are not tilted. In the eighth O site, O(8) is bonded to two equivalent Mg(3), two equivalent Mg(7), one Cu(1), and one Sn(1) atom to form OMg4CuSn octahedra that share corners with two equivalent O(9)Mg6 octahedra, corners with four equivalent O(8)Mg4CuSn octahedra, edges with two equivalent O(4)Mg4Cu2 octahedra, edges with two equivalent O(5)Mg4Sn2 octahedra, edges with two equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(2)Mg5Sn octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the ninth O site, O(9) is bonded to one Mg(1), one Mg(2), two equivalent Mg(4), and two equivalent Mg(7) atoms to form OMg6 octahedra that share corners with two equivalent O(8)Mg4CuSn octahedra, corners with four equivalent O(9)Mg6 octahedra, edges with two equivalent O(1)Mg5Cu octahedra, edges with two equivalent O(2)Mg5Sn octahedra, edges with two equivalent O(6)Mg6 octahedra, edges with two equivalent O(7)Mg6 octahedra, and edges with four equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°.