Sr6Mg(Te4O11)2 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(10), one O(13), one O(15), one O(16), one O(17), one O(18), one O(19), one O(6), and one O(8) atom. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(14), one O(15), one O(16), one O(17), one O(18), one O(20), one O(5), one O(7), and one O(9) atom. In the third Sr site, Sr(3) is bonded in a 7-coordinate geometry to one O(10), one O(11), one O(12), one O(15), one O(17), one O(19), and one O(5) atom. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(16), one O(18), one O(20), one O(6), and one O(9) atom. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one O(1), one O(14), one O(2), one O(22), one O(3), one O(4), one O(6), and one O(9) atom. In the sixth Sr site, Sr(6) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(13), one O(2), one O(21), one O(3), and one O(4) atom. Mg(1) is bonded in a distorted trigonal bipyramidal geometry to one O(13), one O(19), one O(2), one O(3), and one O(4) atom. There are eight inequivalent Te sites. In the first Te site, Te(1) is bonded in a distorted L-shaped geometry to one O(2) and one O(5) atom. In the second Te site, Te(2) is bonded in a distorted T-shaped geometry to one O(1), one O(20), and one O(6) atom. In the third Te site, Te(3) is bonded in a distorted see-saw-like geometry to one O(11), one O(18), one O(22), and one O(7) atom. In the fourth Te site, Te(4) is bonded in a rectangular see-saw-like geometry to one O(12), one O(17), one O(21), and one O(8) atom. In the fifth Te site, Te(5) is bonded in a 3-coordinate geometry to one O(14), one O(15), and one O(21) atom. In the sixth Te site, Te(6) is bonded in a 3-coordinate geometry to one O(13), one O(16), one O(22), and one O(5) atom. In the seventh Te site, Te(7) is bonded in a distorted trigonal non-coplanar geometry to one O(3), one O(8), and one O(9) atom. In the eighth Te site, Te(8) is bonded in a rectangular see-saw-like geometry to one O(10), one O(19), one O(4), and one O(7) atom. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Sr(5), one Sr(6), and one Te(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(5), one Sr(6), one Mg(1), and one Te(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(5), one Sr(6), one Mg(1), and one Te(7) atom. In the fourth O site, O(4) is bonded to one Sr(5), one Sr(6), one Mg(1), and one Te(8) atom to form distorted OSr2MgTe trigonal pyramids that share  a cornercorner with one O(9)Sr3Te tetrahedra and  an edgeedge with one O(19)Sr2MgTe tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(3), one Te(1), and one Te(6) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(4), one Sr(5), and one Te(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Sr(2), one Te(3), and one Te(8) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), one Te(4), and one Te(7) atom. In the ninth O site, O(9) is bonded to one Sr(2), one Sr(4), one Sr(5), and one Te(7) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(15)Sr3Te tetrahedra, corners with two equivalent O(18)Sr3Te tetrahedra,  a cornercorner with one O(4)Sr2MgTe trigonal pyramid,  a cornercorner with one O(17)Sr3Te trigonal pyramid, and  an edgeedge with one O(16)Sr3Te tetrahedra. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Sr(6), and one Te(8) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Sr(3), one Sr(4), and one Te(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one Sr(3), one Sr(4), and one Te(4) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(6), one Mg(1), and one Te(6) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Sr(2), one Sr(5), and one Te(5) atom. In the fifteenth O site, O(15) is bonded to one Sr(1), one Sr(2), one Sr(3), and one Te(5) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(9)Sr3Te tetrahedra, corners with two equivalent O(19)Sr2MgTe tetrahedra, corners with two equivalent O(18)Sr3Te tetrahedra,  a cornercorner with one O(17)Sr3Te trigonal pyramid,  an edgeedge with one O(16)Sr3Te tetrahedra, and  an edgeedge with one O(17)Sr3Te trigonal pyramid. In the sixteenth O site, O(16) is bonded to one Sr(1), one Sr(2), one Sr(4), and one Te(6) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(19)Sr2MgTe tetrahedra,  a cornercorner with one O(18)Sr3Te tetrahedra, corners with two equivalent O(17)Sr3Te trigonal pyramids,  an edgeedge with one O(15)Sr3Te tetrahedra,  an edgeedge with one O(18)Sr3Te tetrahedra, and  an edgeedge with one O(9)Sr3Te tetrahedra. In the seventeenth O site, O(17) is bonded to one Sr(1), one Sr(2), one Sr(3), and one Te(4) atom to form distorted OSr3Te trigonal pyramids that share  a cornercorner with one O(15)Sr3Te tetrahedra,  a cornercorner with one O(9)Sr3Te tetrahedra, corners with two equivalent O(16)Sr3Te tetrahedra,  an edgeedge with one O(19)Sr2MgTe tetrahedra,  an edgeedge with one O(15)Sr3Te tetrahedra, and  an edgeedge with one O(18)Sr3Te tetrahedra. In the eighteenth O site, O(18) is bonded to one Sr(1), one Sr(2), one Sr(4), and one Te(3) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(19)Sr2MgTe tetrahedra,  a cornercorner with one O(16)Sr3Te tetrahedra, corners with two equivalent O(15)Sr3Te tetrahedra, corners with two equivalent O(9)Sr3Te tetrahedra,  an edgeedge with one O(16)Sr3Te tetrahedra, and  an edgeedge with one O(17)Sr3Te trigonal pyramid. In the nineteenth O site, O(19) is bonded to one Sr(1), one Sr(3), one Mg(1), and one Te(8) atom to form OSr2MgTe tetrahedra that share  a cornercorner with one O(16)Sr3Te tetrahedra,  a cornercorner with one O(18)Sr3Te tetrahedra, corners with two equivalent O(15)Sr3Te tetrahedra,  an edgeedge with one O(4)Sr2MgTe trigonal pyramid, and  an edgeedge with one O(17)Sr3Te trigonal pyramid. In the twentieth O site, O(20) is bonded in a distorted trigonal non-coplanar geometry to one Sr(2), one Sr(4), and one Te(2) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Sr(6), one Te(4), and one Te(5) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Sr(5), one Te(3), and one Te(6) atom.
Sr6Mg(Te4O11)2 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(10), one O(13), one O(15), one O(16), one O(17), one O(18), one O(19), one O(6), and one O(8) atom. The Sr(1)-O(10) bond length is 3.00 Å. The Sr(1)-O(13) bond length is 2.87 Å. The Sr(1)-O(15) bond length is 2.63 Å. The Sr(1)-O(16) bond length is 2.58 Å. The Sr(1)-O(17) bond length is 2.63 Å. The Sr(1)-O(18) bond length is 2.77 Å. The Sr(1)-O(19) bond length is 2.52 Å. The Sr(1)-O(6) bond length is 2.86 Å. The Sr(1)-O(8) bond length is 2.76 Å. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(14), one O(15), one O(16), one O(17), one O(18), one O(20), one O(5), one O(7), and one O(9) atom. The Sr(2)-O(14) bond length is 2.73 Å. The Sr(2)-O(15) bond length is 2.72 Å. The Sr(2)-O(16) bond length is 2.75 Å. The Sr(2)-O(17) bond length is 2.83 Å. The Sr(2)-O(18) bond length is 2.61 Å. The Sr(2)-O(20) bond length is 2.74 Å. The Sr(2)-O(5) bond length is 2.68 Å. The Sr(2)-O(7) bond length is 2.68 Å. The Sr(2)-O(9) bond length is 2.94 Å. In the third Sr site, Sr(3) is bonded in a 7-coordinate geometry to one O(10), one O(11), one O(12), one O(15), one O(17), one O(19), and one O(5) atom. The Sr(3)-O(10) bond length is 2.54 Å. The Sr(3)-O(11) bond length is 2.48 Å. The Sr(3)-O(12) bond length is 2.54 Å. The Sr(3)-O(15) bond length is 2.70 Å. The Sr(3)-O(17) bond length is 2.85 Å. The Sr(3)-O(19) bond length is 2.66 Å. The Sr(3)-O(5) bond length is 2.55 Å. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(16), one O(18), one O(20), one O(6), and one O(9) atom. The Sr(4)-O(11) bond length is 2.56 Å. The Sr(4)-O(12) bond length is 2.45 Å. The Sr(4)-O(16) bond length is 2.55 Å. The Sr(4)-O(18) bond length is 2.63 Å. The Sr(4)-O(20) bond length is 2.70 Å. The Sr(4)-O(6) bond length is 2.65 Å. The Sr(4)-O(9) bond length is 2.66 Å. In the fifth Sr site, Sr(5) is bonded in a 8-coordinate geometry to one O(1), one O(14), one O(2), one O(22), one O(3), one O(4), one O(6), and one O(9) atom. The Sr(5)-O(1) bond length is 2.54 Å. The Sr(5)-O(14) bond length is 2.48 Å. The Sr(5)-O(2) bond length is 3.04 Å. The Sr(5)-O(22) bond length is 2.58 Å. The Sr(5)-O(3) bond length is 3.17 Å. The Sr(5)-O(4) bond length is 2.56 Å. The Sr(5)-O(6) bond length is 3.22 Å. The Sr(5)-O(9) bond length is 2.65 Å. In the sixth Sr site, Sr(6) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(13), one O(2), one O(21), one O(3), and one O(4) atom. The Sr(6)-O(1) bond length is 2.49 Å. The Sr(6)-O(10) bond length is 2.80 Å. The Sr(6)-O(13) bond length is 2.66 Å. The Sr(6)-O(2) bond length is 2.62 Å. The Sr(6)-O(21) bond length is 2.80 Å. The Sr(6)-O(3) bond length is 2.69 Å. The Sr(6)-O(4) bond length is 2.78 Å. Mg(1) is bonded in a distorted trigonal bipyramidal geometry to one O(13), one O(19), one O(2), one O(3), and one O(4) atom. The Mg(1)-O(13) bond length is 2.15 Å. The Mg(1)-O(19) bond length is 2.04 Å. The Mg(1)-O(2) bond length is 2.14 Å. The Mg(1)-O(3) bond length is 2.09 Å. The Mg(1)-O(4) bond length is 2.18 Å. There are eight inequivalent Te sites. In the first Te site, Te(1) is bonded in a distorted L-shaped geometry to one O(2) and one O(5) atom. The Te(1)-O(2) bond length is 2.01 Å. The Te(1)-O(5) bond length is 1.94 Å. In the second Te site, Te(2) is bonded in a distorted T-shaped geometry to one O(1), one O(20), and one O(6) atom. The Te(2)-O(1) bond length is 1.91 Å. The Te(2)-O(20) bond length is 1.89 Å. The Te(2)-O(6) bond length is 1.91 Å. In the third Te site, Te(3) is bonded in a distorted see-saw-like geometry to one O(11), one O(18), one O(22), and one O(7) atom. The Te(3)-O(11) bond length is 1.89 Å. The Te(3)-O(18) bond length is 1.90 Å. The Te(3)-O(22) bond length is 2.51 Å. The Te(3)-O(7) bond length is 1.96 Å. In the fourth Te site, Te(4) is bonded in a rectangular see-saw-like geometry to one O(12), one O(17), one O(21), and one O(8) atom. The Te(4)-O(12) bond length is 1.87 Å. The Te(4)-O(17) bond length is 1.89 Å. The Te(4)-O(21) bond length is 2.13 Å. The Te(4)-O(8) bond length is 2.24 Å. In the fifth Te site, Te(5) is bonded in a 3-coordinate geometry to one O(14), one O(15), and one O(21) atom. The Te(5)-O(14) bond length is 1.88 Å. The Te(5)-O(15) bond length is 1.89 Å. The Te(5)-O(21) bond length is 1.97 Å. In the sixth Te site, Te(6) is bonded in a 3-coordinate geometry to one O(13), one O(16), one O(22), and one O(5) atom. The Te(6)-O(13) bond length is 1.93 Å. The Te(6)-O(16) bond length is 1.91 Å. The Te(6)-O(22) bond length is 1.92 Å. The Te(6)-O(5) bond length is 2.69 Å. In the seventh Te site, Te(7) is bonded in a distorted trigonal non-coplanar geometry to one O(3), one O(8), and one O(9) atom. The Te(7)-O(3) bond length is 1.89 Å. The Te(7)-O(8) bond length is 1.94 Å. The Te(7)-O(9) bond length is 1.89 Å. In the eighth Te site, Te(8) is bonded in a rectangular see-saw-like geometry to one O(10), one O(19), one O(4), and one O(7) atom. The Te(8)-O(10) bond length is 1.89 Å. The Te(8)-O(19) bond length is 1.99 Å. The Te(8)-O(4) bond length is 1.92 Å. The Te(8)-O(7) bond length is 2.35 Å. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Sr(5), one Sr(6), and one Te(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(5), one Sr(6), one Mg(1), and one Te(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(5), one Sr(6), one Mg(1), and one Te(7) atom. In the fourth O site, O(4) is bonded to one Sr(5), one Sr(6), one Mg(1), and one Te(8) atom to form distorted OSr2MgTe trigonal pyramids that share  a cornercorner with one O(9)Sr3Te tetrahedra and  an edgeedge with one O(19)Sr2MgTe tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(2), one Sr(3), one Te(1), and one Te(6) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(4), one Sr(5), and one Te(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Sr(2), one Te(3), and one Te(8) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), one Te(4), and one Te(7) atom. In the ninth O site, O(9) is bonded to one Sr(2), one Sr(4), one Sr(5), and one Te(7) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(15)Sr3Te tetrahedra, corners with two equivalent O(18)Sr3Te tetrahedra,  a cornercorner with one O(4)Sr2MgTe trigonal pyramid,  a cornercorner with one O(17)Sr3Te trigonal pyramid, and  an edgeedge with one O(16)Sr3Te tetrahedra. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), one Sr(6), and one Te(8) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Sr(3), one Sr(4), and one Te(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one Sr(3), one Sr(4), and one Te(4) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(6), one Mg(1), and one Te(6) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Sr(2), one Sr(5), and one Te(5) atom. In the fifteenth O site, O(15) is bonded to one Sr(1), one Sr(2), one Sr(3), and one Te(5) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(9)Sr3Te tetrahedra, corners with two equivalent O(19)Sr2MgTe tetrahedra, corners with two equivalent O(18)Sr3Te tetrahedra,  a cornercorner with one O(17)Sr3Te trigonal pyramid,  an edgeedge with one O(16)Sr3Te tetrahedra, and  an edgeedge with one O(17)Sr3Te trigonal pyramid. In the sixteenth O site, O(16) is bonded to one Sr(1), one Sr(2), one Sr(4), and one Te(6) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(19)Sr2MgTe tetrahedra,  a cornercorner with one O(18)Sr3Te tetrahedra, corners with two equivalent O(17)Sr3Te trigonal pyramids,  an edgeedge with one O(15)Sr3Te tetrahedra,  an edgeedge with one O(18)Sr3Te tetrahedra, and  an edgeedge with one O(9)Sr3Te tetrahedra. In the seventeenth O site, O(17) is bonded to one Sr(1), one Sr(2), one Sr(3), and one Te(4) atom to form distorted OSr3Te trigonal pyramids that share  a cornercorner with one O(15)Sr3Te tetrahedra,  a cornercorner with one O(9)Sr3Te tetrahedra, corners with two equivalent O(16)Sr3Te tetrahedra,  an edgeedge with one O(19)Sr2MgTe tetrahedra,  an edgeedge with one O(15)Sr3Te tetrahedra, and  an edgeedge with one O(18)Sr3Te tetrahedra. In the eighteenth O site, O(18) is bonded to one Sr(1), one Sr(2), one Sr(4), and one Te(3) atom to form distorted OSr3Te tetrahedra that share  a cornercorner with one O(19)Sr2MgTe tetrahedra,  a cornercorner with one O(16)Sr3Te tetrahedra, corners with two equivalent O(15)Sr3Te tetrahedra, corners with two equivalent O(9)Sr3Te tetrahedra,  an edgeedge with one O(16)Sr3Te tetrahedra, and  an edgeedge with one O(17)Sr3Te trigonal pyramid. In the nineteenth O site, O(19) is bonded to one Sr(1), one Sr(3), one Mg(1), and one Te(8) atom to form OSr2MgTe tetrahedra that share  a cornercorner with one O(16)Sr3Te tetrahedra,  a cornercorner with one O(18)Sr3Te tetrahedra, corners with two equivalent O(15)Sr3Te tetrahedra,  an edgeedge with one O(4)Sr2MgTe trigonal pyramid, and  an edgeedge with one O(17)Sr3Te trigonal pyramid. In the twentieth O site, O(20) is bonded in a distorted trigonal non-coplanar geometry to one Sr(2), one Sr(4), and one Te(2) atom. In the twenty-first O site, O(21) is bonded in a distorted trigonal planar geometry to one Sr(6), one Te(4), and one Te(5) atom. In the twenty-second O site, O(22) is bonded in a distorted trigonal planar geometry to one Sr(5), one Te(3), and one Te(6) atom.