Ba6Mg11F34 crystallizes in the triclinic P-1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one F(10), one F(11), one F(12), one F(14), one F(4), one F(6), one F(7), and two equivalent F(15) atoms. In the second Ba site, Ba(2) is bonded to one F(10), one F(11), one F(14), one F(16), one F(17), one F(3), one F(4), one F(5), one F(6), one F(8), and two equivalent F(2) atoms to form distorted BaF12 cuboctahedra that share  a cornercorner with one Mg(2)F6 octahedra,  a cornercorner with one Mg(3)F6 octahedra, corners with two equivalent Mg(1)F6 octahedra, corners with two equivalent Mg(6)F6 octahedra,  an edgeedge with one Ba(2)F12 cuboctahedra,  an edgeedge with one Mg(3)F6 octahedra,  an edgeedge with one Mg(4)F6 octahedra,  a faceface with one Mg(1)F6 octahedra,  a faceface with one Mg(2)F6 octahedra,  a faceface with one Mg(4)F6 octahedra, and  a faceface with one Mg(5)F6 octahedra. The corner-sharing octahedral tilt angles range from 26-59°. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one F(1), one F(10), one F(12), one F(15), one F(3), one F(5), one F(7), one F(8), and two equivalent F(16) atoms. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one F(11), one F(13), one F(14), one F(3), one F(4), and one F(5) atom to form MgF6 octahedra that share corners with two equivalent Ba(2)F12 cuboctahedra,  a cornercorner with one Mg(3)F6 octahedra,  a cornercorner with one Mg(4)F6 octahedra, corners with two equivalent Mg(2)F6 octahedra,  an edgeedge with one Mg(6)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 43-51°. In the second Mg site, Mg(2) is bonded to one F(14), one F(15), one F(17), one F(5), one F(6), and one F(9) atom to form MgF6 octahedra that share  a cornercorner with one Ba(2)F12 cuboctahedra, corners with two equivalent Mg(1)F6 octahedra, corners with two equivalent Mg(5)F6 octahedra,  an edgeedge with one Mg(3)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-51°. In the third Mg site, Mg(3) is bonded to one F(1), one F(13), one F(17), one F(2), one F(7), and one F(9) atom to form MgF6 octahedra that share  a cornercorner with one Ba(2)F12 cuboctahedra,  a cornercorner with one Mg(1)F6 octahedra,  a cornercorner with one Mg(6)F6 octahedra,  an edgeedge with one Ba(2)F12 cuboctahedra,  an edgeedge with one Mg(2)F6 octahedra,  an edgeedge with one Mg(4)F6 octahedra, and  an edgeedge with one Mg(5)F6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. In the fourth Mg site, Mg(4) is bonded to one F(12), one F(16), one F(2), one F(4), one F(7), and one F(8) atom to form MgF6 octahedra that share  a cornercorner with one Mg(1)F6 octahedra,  a cornercorner with one Mg(6)F6 octahedra, corners with two equivalent Mg(5)F6 octahedra,  an edgeedge with one Ba(2)F12 cuboctahedra,  an edgeedge with one Mg(3)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 11-47°. In the fifth Mg site, Mg(5) is bonded to one F(1), one F(10), one F(12), one F(16), one F(6), and one F(9) atom to form MgF6 octahedra that share corners with two equivalent Mg(2)F6 octahedra, corners with two equivalent Mg(4)F6 octahedra,  an edgeedge with one Mg(3)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-22°. In the sixth Mg site, Mg(6) is bonded to two equivalent F(13), two equivalent F(3), and two equivalent F(8) atoms to form MgF6 octahedra that share corners with four equivalent Ba(2)F12 cuboctahedra, corners with two equivalent Mg(3)F6 octahedra, corners with two equivalent Mg(4)F6 octahedra, and edges with two equivalent Mg(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 47-50°. There are seventeen inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar geometry to one Ba(3), one Mg(3), and one Mg(5) atom. In the second F site, F(2) is bonded in a distorted water-like geometry to two equivalent Ba(2), one Mg(3), and one Mg(4) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(3), one Mg(1), and one Mg(6) atom. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), and one Mg(4) atom. In the fifth F site, F(5) is bonded in a distorted bent 120 degrees geometry to one Ba(2), one Ba(3), one Mg(1), and one Mg(2) atom. In the sixth F site, F(6) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), one Mg(2), and one Mg(5) atom. In the seventh F site, F(7) is bonded in a distorted water-like geometry to one Ba(1), one Ba(3), one Mg(3), and one Mg(4) atom. In the eighth F site, F(8) is bonded in a 2-coordinate geometry to one Ba(2), one Ba(3), one Mg(4), and one Mg(6) atom. In the ninth F site, F(9) is bonded in a T-shaped geometry to one Mg(2), one Mg(3), and one Mg(5) atom. In the tenth F site, F(10) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), and one Mg(5) atom. In the eleventh F site, F(11) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), and one Mg(1) atom. In the twelfth F site, F(12) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ba(3), one Mg(4), and one Mg(5) atom. In the thirteenth F site, F(13) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(3), and one Mg(6) atom. In the fourteenth F site, F(14) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Mg(1), and one Mg(2) atom. In the fifteenth F site, F(15) is bonded to one Ba(3), two equivalent Ba(1), and one Mg(2) atom to form distorted edge-sharing FBa3Mg tetrahedra. In the sixteenth F site, F(16) is bonded in a distorted linear geometry to one Ba(2), two equivalent Ba(3), one Mg(4), and one Mg(5) atom. In the seventeenth F site, F(17) is bonded in a distorted water-like geometry to one Ba(2), one Mg(2), and one Mg(3) atom.
Ba6Mg11F34 crystallizes in the triclinic P-1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one F(10), one F(11), one F(12), one F(14), one F(4), one F(6), one F(7), and two equivalent F(15) atoms. The Ba(1)-F(10) bond length is 2.78 Å. The Ba(1)-F(11) bond length is 2.63 Å. The Ba(1)-F(12) bond length is 2.98 Å. The Ba(1)-F(14) bond length is 2.88 Å. The Ba(1)-F(4) bond length is 2.72 Å. The Ba(1)-F(6) bond length is 3.05 Å. The Ba(1)-F(7) bond length is 2.89 Å. There is one shorter (2.65 Å) and one longer (2.77 Å) Ba(1)-F(15) bond length. In the second Ba site, Ba(2) is bonded to one F(10), one F(11), one F(14), one F(16), one F(17), one F(3), one F(4), one F(5), one F(6), one F(8), and two equivalent F(2) atoms to form distorted BaF12 cuboctahedra that share  a cornercorner with one Mg(2)F6 octahedra,  a cornercorner with one Mg(3)F6 octahedra, corners with two equivalent Mg(1)F6 octahedra, corners with two equivalent Mg(6)F6 octahedra,  an edgeedge with one Ba(2)F12 cuboctahedra,  an edgeedge with one Mg(3)F6 octahedra,  an edgeedge with one Mg(4)F6 octahedra,  a faceface with one Mg(1)F6 octahedra,  a faceface with one Mg(2)F6 octahedra,  a faceface with one Mg(4)F6 octahedra, and  a faceface with one Mg(5)F6 octahedra. The corner-sharing octahedral tilt angles range from 26-59°. The Ba(2)-F(10) bond length is 2.87 Å. The Ba(2)-F(11) bond length is 2.67 Å. The Ba(2)-F(14) bond length is 3.00 Å. The Ba(2)-F(16) bond length is 3.20 Å. The Ba(2)-F(17) bond length is 2.80 Å. The Ba(2)-F(3) bond length is 2.93 Å. The Ba(2)-F(4) bond length is 2.85 Å. The Ba(2)-F(5) bond length is 2.97 Å. The Ba(2)-F(6) bond length is 3.19 Å. The Ba(2)-F(8) bond length is 3.14 Å. There is one shorter (2.79 Å) and one longer (3.00 Å) Ba(2)-F(2) bond length. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one F(1), one F(10), one F(12), one F(15), one F(3), one F(5), one F(7), one F(8), and two equivalent F(16) atoms. The Ba(3)-F(1) bond length is 2.62 Å. The Ba(3)-F(10) bond length is 2.67 Å. The Ba(3)-F(12) bond length is 2.94 Å. The Ba(3)-F(15) bond length is 2.71 Å. The Ba(3)-F(3) bond length is 2.73 Å. The Ba(3)-F(5) bond length is 2.87 Å. The Ba(3)-F(7) bond length is 2.78 Å. The Ba(3)-F(8) bond length is 2.88 Å. There is one shorter (3.04 Å) and one longer (3.22 Å) Ba(3)-F(16) bond length. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one F(11), one F(13), one F(14), one F(3), one F(4), and one F(5) atom to form MgF6 octahedra that share corners with two equivalent Ba(2)F12 cuboctahedra,  a cornercorner with one Mg(3)F6 octahedra,  a cornercorner with one Mg(4)F6 octahedra, corners with two equivalent Mg(2)F6 octahedra,  an edgeedge with one Mg(6)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 43-51°. The Mg(1)-F(11) bond length is 1.96 Å. The Mg(1)-F(13) bond length is 2.08 Å. The Mg(1)-F(14) bond length is 1.98 Å. The Mg(1)-F(3) bond length is 2.07 Å. The Mg(1)-F(4) bond length is 2.07 Å. The Mg(1)-F(5) bond length is 2.03 Å. In the second Mg site, Mg(2) is bonded to one F(14), one F(15), one F(17), one F(5), one F(6), and one F(9) atom to form MgF6 octahedra that share  a cornercorner with one Ba(2)F12 cuboctahedra, corners with two equivalent Mg(1)F6 octahedra, corners with two equivalent Mg(5)F6 octahedra,  an edgeedge with one Mg(3)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-51°. The Mg(2)-F(14) bond length is 2.00 Å. The Mg(2)-F(15) bond length is 2.00 Å. The Mg(2)-F(17) bond length is 1.99 Å. The Mg(2)-F(5) bond length is 2.00 Å. The Mg(2)-F(6) bond length is 2.03 Å. The Mg(2)-F(9) bond length is 2.07 Å. In the third Mg site, Mg(3) is bonded to one F(1), one F(13), one F(17), one F(2), one F(7), and one F(9) atom to form MgF6 octahedra that share  a cornercorner with one Ba(2)F12 cuboctahedra,  a cornercorner with one Mg(1)F6 octahedra,  a cornercorner with one Mg(6)F6 octahedra,  an edgeedge with one Ba(2)F12 cuboctahedra,  an edgeedge with one Mg(2)F6 octahedra,  an edgeedge with one Mg(4)F6 octahedra, and  an edgeedge with one Mg(5)F6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. The Mg(3)-F(1) bond length is 1.96 Å. The Mg(3)-F(13) bond length is 2.01 Å. The Mg(3)-F(17) bond length is 1.99 Å. The Mg(3)-F(2) bond length is 2.03 Å. The Mg(3)-F(7) bond length is 2.02 Å. The Mg(3)-F(9) bond length is 2.11 Å. In the fourth Mg site, Mg(4) is bonded to one F(12), one F(16), one F(2), one F(4), one F(7), and one F(8) atom to form MgF6 octahedra that share  a cornercorner with one Mg(1)F6 octahedra,  a cornercorner with one Mg(6)F6 octahedra, corners with two equivalent Mg(5)F6 octahedra,  an edgeedge with one Ba(2)F12 cuboctahedra,  an edgeedge with one Mg(3)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 11-47°. The Mg(4)-F(12) bond length is 2.00 Å. The Mg(4)-F(16) bond length is 2.03 Å. The Mg(4)-F(2) bond length is 2.03 Å. The Mg(4)-F(4) bond length is 2.02 Å. The Mg(4)-F(7) bond length is 2.03 Å. The Mg(4)-F(8) bond length is 1.96 Å. In the fifth Mg site, Mg(5) is bonded to one F(1), one F(10), one F(12), one F(16), one F(6), and one F(9) atom to form MgF6 octahedra that share corners with two equivalent Mg(2)F6 octahedra, corners with two equivalent Mg(4)F6 octahedra,  an edgeedge with one Mg(3)F6 octahedra, and  a faceface with one Ba(2)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-22°. The Mg(5)-F(1) bond length is 1.99 Å. The Mg(5)-F(10) bond length is 1.97 Å. The Mg(5)-F(12) bond length is 1.99 Å. The Mg(5)-F(16) bond length is 2.01 Å. The Mg(5)-F(6) bond length is 2.01 Å. The Mg(5)-F(9) bond length is 2.07 Å. In the sixth Mg site, Mg(6) is bonded to two equivalent F(13), two equivalent F(3), and two equivalent F(8) atoms to form MgF6 octahedra that share corners with four equivalent Ba(2)F12 cuboctahedra, corners with two equivalent Mg(3)F6 octahedra, corners with two equivalent Mg(4)F6 octahedra, and edges with two equivalent Mg(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 47-50°. Both Mg(6)-F(13) bond lengths are 2.03 Å. Both Mg(6)-F(3) bond lengths are 1.99 Å. Both Mg(6)-F(8) bond lengths are 2.00 Å. There are seventeen inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar geometry to one Ba(3), one Mg(3), and one Mg(5) atom. In the second F site, F(2) is bonded in a distorted water-like geometry to two equivalent Ba(2), one Mg(3), and one Mg(4) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(3), one Mg(1), and one Mg(6) atom. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), and one Mg(4) atom. In the fifth F site, F(5) is bonded in a distorted bent 120 degrees geometry to one Ba(2), one Ba(3), one Mg(1), and one Mg(2) atom. In the sixth F site, F(6) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), one Mg(2), and one Mg(5) atom. In the seventh F site, F(7) is bonded in a distorted water-like geometry to one Ba(1), one Ba(3), one Mg(3), and one Mg(4) atom. In the eighth F site, F(8) is bonded in a 2-coordinate geometry to one Ba(2), one Ba(3), one Mg(4), and one Mg(6) atom. In the ninth F site, F(9) is bonded in a T-shaped geometry to one Mg(2), one Mg(3), and one Mg(5) atom. In the tenth F site, F(10) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), and one Mg(5) atom. In the eleventh F site, F(11) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), and one Mg(1) atom. In the twelfth F site, F(12) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ba(3), one Mg(4), and one Mg(5) atom. In the thirteenth F site, F(13) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(3), and one Mg(6) atom. In the fourteenth F site, F(14) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Mg(1), and one Mg(2) atom. In the fifteenth F site, F(15) is bonded to one Ba(3), two equivalent Ba(1), and one Mg(2) atom to form distorted edge-sharing FBa3Mg tetrahedra. In the sixteenth F site, F(16) is bonded in a distorted linear geometry to one Ba(2), two equivalent Ba(3), one Mg(4), and one Mg(5) atom. In the seventeenth F site, F(17) is bonded in a distorted water-like geometry to one Ba(2), one Mg(2), and one Mg(3) atom.