CsSi3O7 crystallizes in the orthorhombic P2_12_12_1 space group. Cs(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(5), and two equivalent O(7) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(4), one O(7), and two equivalent O(3) atoms to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Si(1), and one Si(2) atom. In the second O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the third O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one Si(3) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1) and one Si(2) atom. In the fifth O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Si(1), and one Si(2) atom. In the sixth O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Si(3) atoms. In the seventh O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom.
CsSi3O7 crystallizes in the orthorhombic P2_12_12_1 space group. Cs(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(5), and two equivalent O(7) atoms. The Cs(1)-O(1) bond length is 3.10 Å. The Cs(1)-O(2) bond length is 3.24 Å. The Cs(1)-O(5) bond length is 3.19 Å. There is one shorter (3.06 Å) and one longer (3.18 Å) Cs(1)-O(7) bond length. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(4) bond length is 1.62 Å. The Si(1)-O(5) bond length is 1.63 Å. The Si(1)-O(6) bond length is 1.63 Å. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. The Si(2)-O(1) bond length is 1.61 Å. The Si(2)-O(2) bond length is 1.65 Å. The Si(2)-O(5) bond length is 1.65 Å. The Si(2)-O(6) bond length is 1.66 Å. In the third Si site, Si(3) is bonded to one O(4), one O(7), and two equivalent O(3) atoms to form corner-sharing SiO4 tetrahedra. The Si(3)-O(4) bond length is 1.65 Å. The Si(3)-O(7) bond length is 1.62 Å. There is one shorter (1.64 Å) and one longer (1.65 Å) Si(3)-O(3) bond length. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Si(1), and one Si(2) atom. In the second O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the third O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one Si(3) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1) and one Si(2) atom. In the fifth O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Si(1), and one Si(2) atom. In the sixth O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Si(3) atoms. In the seventh O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom.