Na4Y2Si2SO12 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(3), one O(5), one O(7), and one O(9) atom. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(11), one O(12), one O(3), and one O(8) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(10), one O(12), one O(2), one O(4), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form distorted YO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. In the second Y site, Y(2) is bonded to one O(10), one O(11), one O(12), one O(4), one O(5), and one O(6) atom to form YO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(2), one O(5), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-43°. In the second Si site, Si(2) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-43°. S(1) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-36°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Y(1) and one S(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Na(3), one Y(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one Y(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(3), one Y(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Na(1), one Y(2), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Y(2) and one S(1) atom. In the seventh O site, O(7) is bonded to one Na(1), one Na(3), one Na(4), one Y(1), and one Si(2) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids. In the eighth O site, O(8) is bonded to one Na(2), one Na(3), one Na(4), one Y(1), and one Si(1) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids. In the ninth O site, O(9) is bonded in a 1-coordinate geometry to one Na(1), one Na(4), one Y(1), and one S(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Y(2), and one S(1) atom. In the eleventh O site, O(11) is bonded to one Na(1), one Na(2), one Na(4), one Y(2), and one Si(1) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids. In the twelfth O site, O(12) is bonded to one Na(2), one Na(3), one Na(4), one Y(2), and one Si(2) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids.
Na4Y2Si2SO12 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(3), one O(5), one O(7), and one O(9) atom. The Na(1)-O(10) bond length is 2.87 Å. The Na(1)-O(11) bond length is 2.65 Å. The Na(1)-O(3) bond length is 2.97 Å. The Na(1)-O(5) bond length is 2.59 Å. The Na(1)-O(7) bond length is 2.56 Å. The Na(1)-O(9) bond length is 2.79 Å. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(11), one O(12), one O(3), and one O(8) atom. The Na(2)-O(11) bond length is 2.45 Å. The Na(2)-O(12) bond length is 2.65 Å. The Na(2)-O(3) bond length is 2.54 Å. The Na(2)-O(8) bond length is 2.52 Å. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(10), one O(12), one O(2), one O(4), one O(7), and one O(8) atom. The Na(3)-O(10) bond length is 2.79 Å. The Na(3)-O(12) bond length is 2.47 Å. The Na(3)-O(2) bond length is 2.86 Å. The Na(3)-O(4) bond length is 2.67 Å. The Na(3)-O(7) bond length is 2.53 Å. The Na(3)-O(8) bond length is 2.66 Å. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom. The Na(4)-O(10) bond length is 2.91 Å. The Na(4)-O(11) bond length is 2.59 Å. The Na(4)-O(12) bond length is 2.45 Å. The Na(4)-O(7) bond length is 2.45 Å. The Na(4)-O(8) bond length is 2.62 Å. The Na(4)-O(9) bond length is 2.94 Å. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form distorted YO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. The Y(1)-O(1) bond length is 2.39 Å. The Y(1)-O(2) bond length is 2.13 Å. The Y(1)-O(3) bond length is 2.19 Å. The Y(1)-O(7) bond length is 2.27 Å. The Y(1)-O(8) bond length is 2.20 Å. The Y(1)-O(9) bond length is 2.44 Å. In the second Y site, Y(2) is bonded to one O(10), one O(11), one O(12), one O(4), one O(5), and one O(6) atom to form YO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent S(1)O4 tetrahedra. The Y(2)-O(10) bond length is 2.36 Å. The Y(2)-O(11) bond length is 2.26 Å. The Y(2)-O(12) bond length is 2.28 Å. The Y(2)-O(4) bond length is 2.18 Å. The Y(2)-O(5) bond length is 2.19 Å. The Y(2)-O(6) bond length is 2.31 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(2), one O(5), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-43°. The Si(1)-O(11) bond length is 1.65 Å. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(5) bond length is 1.64 Å. The Si(1)-O(8) bond length is 1.65 Å. In the second Si site, Si(2) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-43°. The Si(2)-O(12) bond length is 1.65 Å. The Si(2)-O(3) bond length is 1.64 Å. The Si(2)-O(4) bond length is 1.64 Å. The Si(2)-O(7) bond length is 1.66 Å. S(1) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-36°. The S(1)-O(1) bond length is 1.48 Å. The S(1)-O(10) bond length is 1.49 Å. The S(1)-O(6) bond length is 1.48 Å. The S(1)-O(9) bond length is 1.48 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Y(1) and one S(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Na(3), one Y(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one Y(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(3), one Y(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Na(1), one Y(2), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Y(2) and one S(1) atom. In the seventh O site, O(7) is bonded to one Na(1), one Na(3), one Na(4), one Y(1), and one Si(2) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids. In the eighth O site, O(8) is bonded to one Na(2), one Na(3), one Na(4), one Y(1), and one Si(1) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids. In the ninth O site, O(9) is bonded in a 1-coordinate geometry to one Na(1), one Na(4), one Y(1), and one S(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Y(2), and one S(1) atom. In the eleventh O site, O(11) is bonded to one Na(1), one Na(2), one Na(4), one Y(2), and one Si(1) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids. In the twelfth O site, O(12) is bonded to one Na(2), one Na(3), one Na(4), one Y(2), and one Si(2) atom to form a mixture of distorted corner, face, and edge-sharing ONa3YSi trigonal bipyramids.