CsAlSi5O12 is Low Tridymite-derived structured and crystallizes in the monoclinic Cc space group. Cs(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(7), two equivalent O(11), and two equivalent O(3) atoms. Al(1) is bonded to one O(1), one O(3), one O(7), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(10), one O(11), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(2), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(11), one O(3), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(12), one O(4), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the fifth Si site, Si(5) is bonded to one O(2), one O(4), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Cs(1), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Si(2), and one Si(5) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Cs(1), one Al(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(4) and one Si(5) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Cs(1), one Al(1), and one Si(5) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(5) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to two equivalent Cs(1), one Si(1), and one Si(3) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom.
CsAlSi5O12 is Low Tridymite-derived structured and crystallizes in the monoclinic Cc space group. Cs(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(7), two equivalent O(11), and two equivalent O(3) atoms. The Cs(1)-O(1) bond length is 3.09 Å. The Cs(1)-O(2) bond length is 3.58 Å. The Cs(1)-O(7) bond length is 3.33 Å. There is one shorter (3.56 Å) and one longer (3.73 Å) Cs(1)-O(11) bond length. There is one shorter (3.47 Å) and one longer (3.59 Å) Cs(1)-O(3) bond length. Al(1) is bonded to one O(1), one O(3), one O(7), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)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(3) bond length is 1.75 Å. The Al(1)-O(7) bond length is 1.76 Å. The Al(1)-O(8) bond length is 1.72 Å. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(10), one O(11), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. The Si(1)-O(1) bond length is 1.62 Å. The Si(1)-O(10) bond length is 1.65 Å. The Si(1)-O(11) bond length is 1.65 Å. The Si(1)-O(8) bond length is 1.59 Å. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(2), and one O(9) atom to form corner-sharing SiO4 tetrahedra. The Si(2)-O(10) bond length is 1.61 Å. The Si(2)-O(12) bond length is 1.64 Å. The Si(2)-O(2) bond length is 1.64 Å. The Si(2)-O(9) bond length is 1.63 Å. In the third Si site, Si(3) is bonded to one O(11), one O(3), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. The Si(3)-O(11) bond length is 1.63 Å. The Si(3)-O(3) bond length is 1.60 Å. The Si(3)-O(5) bond length is 1.64 Å. The Si(3)-O(6) bond length is 1.65 Å. In the fourth Si site, Si(4) is bonded to one O(12), one O(4), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. The Si(4)-O(12) bond length is 1.64 Å. The Si(4)-O(4) bond length is 1.63 Å. The Si(4)-O(5) bond length is 1.62 Å. The Si(4)-O(6) bond length is 1.63 Å. In the fifth Si site, Si(5) is bonded to one O(2), one O(4), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The Si(5)-O(2) bond length is 1.65 Å. The Si(5)-O(4) bond length is 1.64 Å. The Si(5)-O(7) bond length is 1.60 Å. The Si(5)-O(9) bond length is 1.64 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Cs(1), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Si(2), and one Si(5) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Cs(1), one Al(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(4) and one Si(5) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Cs(1), one Al(1), and one Si(5) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(5) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to two equivalent Cs(1), one Si(1), and one Si(3) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom.