Cs5AgSi3O9 crystallizes in the monoclinic P2_1/m space group. There are five inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(5), and four equivalent O(1) atoms. In the third Cs site, Cs(3) is bonded in a 2-coordinate geometry to two equivalent O(1) atoms. In the fourth Cs site, Cs(4) is bonded in a 2-coordinate geometry to two equivalent O(3) atoms. In the fifth Cs site, Cs(5) is bonded in a 9-coordinate geometry to two equivalent O(3), three equivalent O(6), and four equivalent O(1) atoms. Ag(1) is bonded in a linear geometry to two equivalent O(2) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(4), one O(5), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(4), one O(6), and two equivalent O(3) atoms to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(5), one O(6), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cs(3), two equivalent Cs(2), two equivalent Cs(5), and one Si(3) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Cs(1), one Cs(2), one Ag(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(4), one Cs(5), two equivalent Cs(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(1), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to three equivalent Cs(2), one Si(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to three equivalent Cs(5), one Si(2), and one Si(3) atom.
Cs5AgSi3O9 crystallizes in the monoclinic P2_1/m space group. There are five inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms. Both Cs(1)-O(2) bond lengths are 3.57 Å. Both Cs(1)-O(4) bond lengths are 3.48 Å. There are two shorter (3.03 Å) and two longer (3.33 Å) Cs(1)-O(3) bond lengths. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(5), and four equivalent O(1) atoms. Both Cs(2)-O(2) bond lengths are 3.20 Å. There are two shorter (3.43 Å) and one longer (3.61 Å) Cs(2)-O(5) bond length. There are two shorter (3.18 Å) and two longer (3.37 Å) Cs(2)-O(1) bond lengths. In the third Cs site, Cs(3) is bonded in a 2-coordinate geometry to two equivalent O(1) atoms. Both Cs(3)-O(1) bond lengths are 2.86 Å. In the fourth Cs site, Cs(4) is bonded in a 2-coordinate geometry to two equivalent O(3) atoms. Both Cs(4)-O(3) bond lengths are 2.80 Å. In the fifth Cs site, Cs(5) is bonded in a 9-coordinate geometry to two equivalent O(3), three equivalent O(6), and four equivalent O(1) atoms. Both Cs(5)-O(3) bond lengths are 3.30 Å. There is one shorter (3.36 Å) and two longer (3.42 Å) Cs(5)-O(6) bond lengths. There are two shorter (3.12 Å) and two longer (3.48 Å) Cs(5)-O(1) bond lengths. Ag(1) is bonded in a linear geometry to two equivalent O(2) atoms. Both Ag(1)-O(2) bond lengths are 2.07 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(4), one O(5), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. The Si(1)-O(4) bond length is 1.67 Å. The Si(1)-O(5) bond length is 1.66 Å. Both Si(1)-O(2) bond lengths are 1.64 Å. In the second Si site, Si(2) is bonded to one O(4), one O(6), and two equivalent O(3) atoms to form corner-sharing SiO4 tetrahedra. The Si(2)-O(4) bond length is 1.72 Å. The Si(2)-O(6) bond length is 1.69 Å. Both Si(2)-O(3) bond lengths are 1.62 Å. In the third Si site, Si(3) is bonded to one O(5), one O(6), and two equivalent O(1) atoms to form corner-sharing SiO4 tetrahedra. The Si(3)-O(5) bond length is 1.71 Å. The Si(3)-O(6) bond length is 1.69 Å. Both Si(3)-O(1) bond lengths are 1.61 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cs(3), two equivalent Cs(2), two equivalent Cs(5), and one Si(3) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Cs(1), one Cs(2), one Ag(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(4), one Cs(5), two equivalent Cs(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(1), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to three equivalent Cs(2), one Si(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to three equivalent Cs(5), one Si(2), and one Si(3) atom.