Na4Al3Si3O16Cl crystallizes in the monoclinic P2 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one O(2), one O(3), and one O(7) atom. In the second Na site, Na(2) is bonded to one O(1), one O(4), one O(5), and one O(6) atom to form distorted NaO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Cl(2)O4 tetrahedra. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(10), one O(11), one O(15), and one O(9) atom. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one O(12), one O(13), one O(14), one O(16), and one O(8) atom. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(12), one O(15), and one O(3) atom to form AlO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form AlO4 tetrahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the third Al site, Al(3) is bonded to one O(11), one O(4), one O(7), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the fourth Al site, Al(4) is bonded to two equivalent O(10) and two equivalent O(13) atoms to form AlO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(3)O4 tetrahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(13), one O(15), and one O(2) atom to form SiO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(3)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(10), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra, and corners with two equivalent Al(3)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to two equivalent O(11) and two equivalent O(12) atoms to form SiO4 tetrahedra that share corners with two equivalent Al(1)O4 tetrahedra and corners with two equivalent Al(3)O4 tetrahedra. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(2), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Al(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Al(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(2), one Al(3), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Na(2), one Al(2), and one Si(3) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(2) and one Cl(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(1), one Al(3), and one Si(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Na(4), one Al(3), and one Si(3) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Na(3) and one Cl(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(3), one Al(4), and one Si(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(3), one Al(3), and one Si(4) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Na(4), one Al(1), and one Si(4) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Na(4), one Al(4), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a distorted water-like geometry to one Na(4) and one Cl(1) atom. In the fifteenth O site, O(15) is bonded in a 3-coordinate geometry to one Na(3), one Al(1), and one Si(1) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Na(4) and one Cl(1) atom. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a distorted see-saw-like geometry to two equivalent O(14) and two equivalent O(16) atoms. In the second Cl site, Cl(2) is bonded to two equivalent O(6) and two equivalent O(9) atoms to form ClO4 tetrahedra that share corners with two equivalent Na(2)O4 tetrahedra.
Na4Al3Si3O16Cl crystallizes in the monoclinic P2 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one O(2), one O(3), and one O(7) atom. The Na(1)-O(2) bond length is 2.34 Å. The Na(1)-O(3) bond length is 2.36 Å. The Na(1)-O(7) bond length is 2.40 Å. In the second Na site, Na(2) is bonded to one O(1), one O(4), one O(5), and one O(6) atom to form distorted NaO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Cl(2)O4 tetrahedra. The Na(2)-O(1) bond length is 2.38 Å. The Na(2)-O(4) bond length is 2.38 Å. The Na(2)-O(5) bond length is 2.39 Å. The Na(2)-O(6) bond length is 2.44 Å. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(10), one O(11), one O(15), and one O(9) atom. The Na(3)-O(10) bond length is 2.39 Å. The Na(3)-O(11) bond length is 2.37 Å. The Na(3)-O(15) bond length is 2.37 Å. The Na(3)-O(9) bond length is 2.38 Å. In the fourth Na site, Na(4) is bonded in a 4-coordinate geometry to one O(12), one O(13), one O(14), one O(16), and one O(8) atom. The Na(4)-O(12) bond length is 2.40 Å. The Na(4)-O(13) bond length is 2.39 Å. The Na(4)-O(14) bond length is 2.77 Å. The Na(4)-O(16) bond length is 2.37 Å. The Na(4)-O(8) bond length is 2.41 Å. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(12), one O(15), and one O(3) atom to form AlO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The Al(1)-O(1) bond length is 1.75 Å. The Al(1)-O(12) bond length is 1.76 Å. The Al(1)-O(15) bond length is 1.75 Å. The Al(1)-O(3) bond length is 1.76 Å. In the second Al site, Al(2) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form AlO4 tetrahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. Both Al(2)-O(2) bond lengths are 1.76 Å. Both Al(2)-O(5) bond lengths are 1.76 Å. In the third Al site, Al(3) is bonded to one O(11), one O(4), one O(7), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. The Al(3)-O(11) bond length is 1.75 Å. The Al(3)-O(4) bond length is 1.76 Å. The Al(3)-O(7) bond length is 1.76 Å. The Al(3)-O(8) bond length is 1.75 Å. In the fourth Al site, Al(4) is bonded to two equivalent O(10) and two equivalent O(13) atoms to form AlO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(3)O4 tetrahedra. Both Al(4)-O(10) bond lengths are 1.76 Å. Both Al(4)-O(13) bond lengths are 1.75 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(13), one O(15), and one O(2) atom to form SiO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. The Si(1)-O(1) bond length is 1.64 Å. The Si(1)-O(13) bond length is 1.63 Å. The Si(1)-O(15) bond length is 1.64 Å. The Si(1)-O(2) bond length is 1.65 Å. In the second Si site, Si(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Na(2)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(3)O4 tetrahedra. Both Si(2)-O(3) bond lengths are 1.64 Å. Both Si(2)-O(4) bond lengths are 1.64 Å. In the third Si site, Si(3) is bonded to one O(10), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Na(2)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra, and corners with two equivalent Al(3)O4 tetrahedra. The Si(3)-O(10) bond length is 1.63 Å. The Si(3)-O(5) bond length is 1.64 Å. The Si(3)-O(7) bond length is 1.64 Å. The Si(3)-O(8) bond length is 1.64 Å. In the fourth Si site, Si(4) is bonded to two equivalent O(11) and two equivalent O(12) atoms to form SiO4 tetrahedra that share corners with two equivalent Al(1)O4 tetrahedra and corners with two equivalent Al(3)O4 tetrahedra. Both Si(4)-O(11) bond lengths are 1.64 Å. Both Si(4)-O(12) bond lengths are 1.64 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(2), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Al(2), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Al(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(2), one Al(3), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Na(2), one Al(2), and one Si(3) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(2) and one Cl(2) atom. The O(6)-Cl(2) bond length is 1.47 Å. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(1), one Al(3), and one Si(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Na(4), one Al(3), and one Si(3) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Na(3) and one Cl(2) atom. The O(9)-Cl(2) bond length is 1.46 Å. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(3), one Al(4), and one Si(3) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Na(3), one Al(3), and one Si(4) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Na(4), one Al(1), and one Si(4) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Na(4), one Al(4), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a distorted water-like geometry to one Na(4) and one Cl(1) atom. The O(14)-Cl(1) bond length is 1.53 Å. In the fifteenth O site, O(15) is bonded in a 3-coordinate geometry to one Na(3), one Al(1), and one Si(1) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Na(4) and one Cl(1) atom. The O(16)-Cl(1) bond length is 1.73 Å. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a distorted see-saw-like geometry to two equivalent O(14) and two equivalent O(16) atoms. In the second Cl site, Cl(2) is bonded to two equivalent O(6) and two equivalent O(9) atoms to form ClO4 tetrahedra that share corners with two equivalent Na(2)O4 tetrahedra.