Na3Mg4ScSi8(O11F)2 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(12), one O(14), one O(19), one O(2), one O(5), and one O(8) atom. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(16), one O(18), one O(21), and one O(4) atom. In the third Na site, Na(3) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(13), one O(16), one O(20), one O(22), one O(3), and one O(7) atom. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(15), one O(17), one O(6), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Sc(1)O6 octahedra, edges with two equivalent Mg(2)O4F2 octahedra, and edges with two equivalent Mg(3)O4F2 octahedra. In the second Mg site, Mg(2) is bonded to one O(14), one O(17), one O(5), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra,  an edgeedge with one Mg(3)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Sc(1)O6 octahedra. In the third Mg site, Mg(3) is bonded to one O(10), one O(15), one O(18), one O(6), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(2)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Mg(4)O6 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(15), one O(18), one O(21), one O(4), and one O(6) atom to form distorted MgO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra,  an edgeedge with one Mg(1)O4F2 octahedra, and edges with two equivalent Mg(3)O4F2 octahedra. Sc(1) is bonded to one O(14), one O(17), one O(19), one O(2), one O(5), and one O(9) atom to form distorted ScO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra,  an edgeedge with one Mg(1)O4F2 octahedra, and edges with two equivalent Mg(2)O4F2 octahedra. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(10), one O(2), one O(20), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. In the second Si site, Si(2) is bonded to one O(11), one O(22), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-56°. In the third Si site, Si(3) is bonded to one O(1), one O(12), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-62°. In the fourth Si site, Si(4) is bonded to one O(16), one O(3), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Sc(1)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-61°. In the fifth Si site, Si(5) is bonded to one O(13), one O(15), one O(20), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(6)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-62°. In the sixth Si site, Si(6) is bonded to one O(11), one O(13), one O(17), and one O(22) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Sc(1)O6 octahedra,  a cornercorner with one Si(5)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-61°. In the seventh Si site, Si(7) is bonded to one O(1), one O(12), one O(18), and one O(19) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. In the eighth Si site, Si(8) is bonded to one O(14), one O(16), one O(21), and one O(3) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-57°. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Na(3), one Si(3), and one Si(7) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Sc(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Na(3), one Si(4), and one Si(8) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Na(2), one Mg(4), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Mg(2), one Sc(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), one Mg(4), and one Si(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(3), one Si(3), and one Si(4) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one Si(5) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Sc(1), and one Si(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Na(2), one Mg(3), one Mg(4), and one Si(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(2), one Si(2), and one Si(6) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Na(1), one Na(3), one Si(3), and one Si(7) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Na(3), one Si(5), and one Si(6) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Na(1), one Mg(2), one Sc(1), and one Si(8) atom. In the fifteenth O site, O(15) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), one Mg(4), and one Si(5) atom. In the sixteenth O site, O(16) is bonded in a 2-coordinate geometry to one Na(2), one Na(3), one Si(4), and one Si(8) atom. In the seventeenth O site, O(17) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Sc(1), and one Si(6) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Na(2), one Mg(3), one Mg(4), and one Si(7) atom. In the nineteenth O site, O(19) is bonded in a distorted T-shaped geometry to one Na(1), one Sc(1), and one Si(7) atom. In the twentieth O site, O(20) is bonded in a 2-coordinate geometry to one Na(3), one Si(1), and one Si(5) atom. In the twenty-first O site, O(21) is bonded in a distorted T-shaped geometry to one Na(2), one Mg(4), and one Si(8) atom. In the twenty-second O site, O(22) is bonded in a distorted bent 150 degrees geometry to one Na(3), one Si(2), and one Si(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one Mg(3) atom. In the second F site, F(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one Mg(3) atom.
Na3Mg4ScSi8(O11F)2 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(12), one O(14), one O(19), one O(2), one O(5), and one O(8) atom. The Na(1)-O(12) bond length is 2.52 Å. The Na(1)-O(14) bond length is 2.52 Å. The Na(1)-O(19) bond length is 2.38 Å. The Na(1)-O(2) bond length is 2.39 Å. The Na(1)-O(5) bond length is 2.54 Å. The Na(1)-O(8) bond length is 2.48 Å. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(16), one O(18), one O(21), and one O(4) atom. The Na(2)-O(10) bond length is 2.46 Å. The Na(2)-O(11) bond length is 2.59 Å. The Na(2)-O(16) bond length is 2.63 Å. The Na(2)-O(18) bond length is 2.45 Å. The Na(2)-O(21) bond length is 2.38 Å. The Na(2)-O(4) bond length is 2.38 Å. In the third Na site, Na(3) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(13), one O(16), one O(20), one O(22), one O(3), and one O(7) atom. The Na(3)-O(1) bond length is 2.76 Å. The Na(3)-O(12) bond length is 2.97 Å. The Na(3)-O(13) bond length is 2.40 Å. The Na(3)-O(16) bond length is 2.96 Å. The Na(3)-O(20) bond length is 2.89 Å. The Na(3)-O(22) bond length is 2.90 Å. The Na(3)-O(3) bond length is 2.78 Å. The Na(3)-O(7) bond length is 2.55 Å. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(15), one O(17), one O(6), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Sc(1)O6 octahedra, edges with two equivalent Mg(2)O4F2 octahedra, and edges with two equivalent Mg(3)O4F2 octahedra. The Mg(1)-O(15) bond length is 2.05 Å. The Mg(1)-O(17) bond length is 2.11 Å. The Mg(1)-O(6) bond length is 2.06 Å. The Mg(1)-O(9) bond length is 2.11 Å. The Mg(1)-F(1) bond length is 2.04 Å. The Mg(1)-F(2) bond length is 2.05 Å. In the second Mg site, Mg(2) is bonded to one O(14), one O(17), one O(5), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra,  an edgeedge with one Mg(3)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Sc(1)O6 octahedra. The Mg(2)-O(14) bond length is 2.08 Å. The Mg(2)-O(17) bond length is 2.10 Å. The Mg(2)-O(5) bond length is 2.08 Å. The Mg(2)-O(9) bond length is 2.10 Å. The Mg(2)-F(1) bond length is 2.05 Å. The Mg(2)-F(2) bond length is 2.07 Å. In the third Mg site, Mg(3) is bonded to one O(10), one O(15), one O(18), one O(6), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(2)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Mg(4)O6 octahedra. The Mg(3)-O(10) bond length is 2.04 Å. The Mg(3)-O(15) bond length is 2.10 Å. The Mg(3)-O(18) bond length is 2.03 Å. The Mg(3)-O(6) bond length is 2.10 Å. The Mg(3)-F(1) bond length is 2.10 Å. The Mg(3)-F(2) bond length is 2.12 Å. In the fourth Mg site, Mg(4) is bonded to one O(10), one O(15), one O(18), one O(21), one O(4), and one O(6) atom to form distorted MgO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra,  an edgeedge with one Mg(1)O4F2 octahedra, and edges with two equivalent Mg(3)O4F2 octahedra. The Mg(4)-O(10) bond length is 2.10 Å. The Mg(4)-O(15) bond length is 2.29 Å. The Mg(4)-O(18) bond length is 2.10 Å. The Mg(4)-O(21) bond length is 2.02 Å. The Mg(4)-O(4) bond length is 2.01 Å. The Mg(4)-O(6) bond length is 2.29 Å. Sc(1) is bonded to one O(14), one O(17), one O(19), one O(2), one O(5), and one O(9) atom to form distorted ScO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra,  an edgeedge with one Mg(1)O4F2 octahedra, and edges with two equivalent Mg(2)O4F2 octahedra. The Sc(1)-O(14) bond length is 2.12 Å. The Sc(1)-O(17) bond length is 2.29 Å. The Sc(1)-O(19) bond length is 2.00 Å. The Sc(1)-O(2) bond length is 2.00 Å. The Sc(1)-O(5) bond length is 2.11 Å. The Sc(1)-O(9) bond length is 2.29 Å. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(10), one O(2), one O(20), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. The Si(1)-O(10) bond length is 1.62 Å. The Si(1)-O(2) bond length is 1.62 Å. The Si(1)-O(20) bond length is 1.67 Å. The Si(1)-O(8) bond length is 1.68 Å. In the second Si site, Si(2) is bonded to one O(11), one O(22), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-56°. The Si(2)-O(11) bond length is 1.68 Å. The Si(2)-O(22) bond length is 1.68 Å. The Si(2)-O(4) bond length is 1.59 Å. The Si(2)-O(5) bond length is 1.65 Å. In the third Si site, Si(3) is bonded to one O(1), one O(12), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-62°. The Si(3)-O(1) bond length is 1.64 Å. The Si(3)-O(12) bond length is 1.65 Å. The Si(3)-O(6) bond length is 1.62 Å. The Si(3)-O(7) bond length is 1.66 Å. In the fourth Si site, Si(4) is bonded to one O(16), one O(3), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Sc(1)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-61°. The Si(4)-O(16) bond length is 1.64 Å. The Si(4)-O(3) bond length is 1.64 Å. The Si(4)-O(7) bond length is 1.65 Å. The Si(4)-O(9) bond length is 1.64 Å. In the fifth Si site, Si(5) is bonded to one O(13), one O(15), one O(20), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(6)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-62°. The Si(5)-O(13) bond length is 1.66 Å. The Si(5)-O(15) bond length is 1.62 Å. The Si(5)-O(20) bond length is 1.64 Å. The Si(5)-O(8) bond length is 1.64 Å. In the sixth Si site, Si(6) is bonded to one O(11), one O(13), one O(17), and one O(22) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Sc(1)O6 octahedra,  a cornercorner with one Si(5)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-61°. The Si(6)-O(11) bond length is 1.63 Å. The Si(6)-O(13) bond length is 1.65 Å. The Si(6)-O(17) bond length is 1.64 Å. The Si(6)-O(22) bond length is 1.64 Å. In the seventh Si site, Si(7) is bonded to one O(1), one O(12), one O(18), and one O(19) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-56°. The Si(7)-O(1) bond length is 1.68 Å. The Si(7)-O(12) bond length is 1.69 Å. The Si(7)-O(18) bond length is 1.61 Å. The Si(7)-O(19) bond length is 1.62 Å. In the eighth Si site, Si(8) is bonded to one O(14), one O(16), one O(21), and one O(3) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Sc(1)O6 octahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-57°. The Si(8)-O(14) bond length is 1.65 Å. The Si(8)-O(16) bond length is 1.69 Å. The Si(8)-O(21) bond length is 1.58 Å. The Si(8)-O(3) bond length is 1.68 Å. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Na(3), one Si(3), and one Si(7) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Sc(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Na(3), one Si(4), and one Si(8) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Na(2), one Mg(4), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Mg(2), one Sc(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), one Mg(4), and one Si(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(3), one Si(3), and one Si(4) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one Si(5) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Sc(1), and one Si(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Na(2), one Mg(3), one Mg(4), and one Si(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(2), one Si(2), and one Si(6) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Na(1), one Na(3), one Si(3), and one Si(7) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Na(3), one Si(5), and one Si(6) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Na(1), one Mg(2), one Sc(1), and one Si(8) atom. In the fifteenth O site, O(15) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), one Mg(4), and one Si(5) atom. In the sixteenth O site, O(16) is bonded in a 2-coordinate geometry to one Na(2), one Na(3), one Si(4), and one Si(8) atom. In the seventeenth O site, O(17) is bonded in a 4-coordinate geometry to one Mg(1), one Mg(2), one Sc(1), and one Si(6) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Na(2), one Mg(3), one Mg(4), and one Si(7) atom. In the nineteenth O site, O(19) is bonded in a distorted T-shaped geometry to one Na(1), one Sc(1), and one Si(7) atom. In the twentieth O site, O(20) is bonded in a 2-coordinate geometry to one Na(3), one Si(1), and one Si(5) atom. In the twenty-first O site, O(21) is bonded in a distorted T-shaped geometry to one Na(2), one Mg(4), and one Si(8) atom. In the twenty-second O site, O(22) is bonded in a distorted bent 150 degrees geometry to one Na(3), one Si(2), and one Si(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one Mg(3) atom. In the second F site, F(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one Mg(3) atom.