Cs4Sn23 crystallizes in the cubic Pm-3n space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 12-coordinate geometry to four equivalent Sn(2) and eight equivalent Sn(1) atoms. In the second Cs site, Cs(2) is bonded in a 20-coordinate geometry to eight equivalent Sn(3) and twelve equivalent Sn(1) atoms. There are three inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 7-coordinate geometry to one Cs(2), two equivalent Cs(1), one Sn(1), one Sn(2), and two equivalent Sn(3) atoms. In the second Sn site, Sn(2) is bonded to four equivalent Cs(1) and four equivalent Sn(1) atoms to form a mixture of distorted corner and edge-sharing SnCs4Sn4 tetrahedra. In the third Sn site, Sn(3) is bonded in a 5-coordinate geometry to one Cs(2), one Sn(3), and three equivalent Sn(1) atoms.
Cs4Sn23 crystallizes in the cubic Pm-3n space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 12-coordinate geometry to four equivalent Sn(2) and eight equivalent Sn(1) atoms. All Cs(1)-Sn(2) bond lengths are 4.45 Å. All Cs(1)-Sn(1) bond lengths are 4.24 Å. In the second Cs site, Cs(2) is bonded in a 20-coordinate geometry to eight equivalent Sn(3) and twelve equivalent Sn(1) atoms. All Cs(2)-Sn(3) bond lengths are 4.02 Å. All Cs(2)-Sn(1) bond lengths are 4.15 Å. There are three inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 7-coordinate geometry to one Cs(2), two equivalent Cs(1), one Sn(1), one Sn(2), and two equivalent Sn(3) atoms. The Sn(1)-Sn(1) bond length is 2.98 Å. The Sn(1)-Sn(2) bond length is 2.94 Å. Both Sn(1)-Sn(3) bond lengths are 2.91 Å. In the second Sn site, Sn(2) is bonded to four equivalent Cs(1) and four equivalent Sn(1) atoms to form a mixture of distorted corner and edge-sharing SnCs4Sn4 tetrahedra. In the third Sn site, Sn(3) is bonded in a 5-coordinate geometry to one Cs(2), one Sn(3), and three equivalent Sn(1) atoms. The Sn(3)-Sn(3) bond length is 2.87 Å.