Cs2CdI4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to two equivalent I(2), three equivalent I(3), and four equivalent I(1) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one I(3), three equivalent I(2), and four equivalent I(1) atoms. Cd(1) is bonded in a tetrahedral geometry to one I(2), one I(3), and two equivalent I(1) atoms. There are three inequivalent I sites. In the first I site, I(1) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Cd(1) atom to form a mixture of distorted edge, face, and corner-sharing ICs4Cd square pyramids. In the second I site, I(2) is bonded in a 6-coordinate geometry to two equivalent Cs(1), three equivalent Cs(2), and one Cd(1) atom. In the third I site, I(3) is bonded in a 3-coordinate geometry to one Cs(2), three equivalent Cs(1), and one Cd(1) atom.
Cs2CdI4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to two equivalent I(2), three equivalent I(3), and four equivalent I(1) atoms. There is one shorter (3.88 Å) and one longer (3.94 Å) Cs(1)-I(2) bond length. There is one shorter (3.94 Å) and two longer (4.50 Å) Cs(1)-I(3) bond lengths. There are two shorter (3.96 Å) and two longer (3.98 Å) Cs(1)-I(1) bond lengths. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one I(3), three equivalent I(2), and four equivalent I(1) atoms. The Cs(2)-I(3) bond length is 3.93 Å. There is one shorter (4.21 Å) and two longer (4.38 Å) Cs(2)-I(2) bond lengths. There are two shorter (4.05 Å) and two longer (4.09 Å) Cs(2)-I(1) bond lengths. Cd(1) is bonded in a tetrahedral geometry to one I(2), one I(3), and two equivalent I(1) atoms. The Cd(1)-I(2) bond length is 2.81 Å. The Cd(1)-I(3) bond length is 2.78 Å. Both Cd(1)-I(1) bond lengths are 2.80 Å. There are three inequivalent I sites. In the first I site, I(1) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Cd(1) atom to form a mixture of distorted edge, face, and corner-sharing ICs4Cd square pyramids. In the second I site, I(2) is bonded in a 6-coordinate geometry to two equivalent Cs(1), three equivalent Cs(2), and one Cd(1) atom. In the third I site, I(3) is bonded in a 3-coordinate geometry to one Cs(2), three equivalent Cs(1), and one Cd(1) atom.