RbSnI3 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 9-coordinate geometry to two equivalent I(2), three equivalent I(3), and four equivalent I(1) atoms. Sn(1) is bonded to one I(1), two equivalent I(3), and three equivalent I(2) atoms to form edge-sharing SnI6 octahedra. There are three inequivalent I sites. In the first I site, I(1) is bonded to four equivalent Rb(1) and one Sn(1) atom to form distorted IRb4Sn square pyramids that share corners with four equivalent I(1)Rb4Sn square pyramids, corners with three equivalent I(2)Rb2Sn3 trigonal bipyramids, corners with six equivalent I(3)Rb3Sn2 trigonal bipyramids, edges with four equivalent I(1)Rb4Sn square pyramids, edges with four equivalent I(2)Rb2Sn3 trigonal bipyramids, and edges with four equivalent I(3)Rb3Sn2 trigonal bipyramids. In the second I site, I(2) is bonded to two equivalent Rb(1) and three equivalent Sn(1) atoms to form distorted IRb2Sn3 trigonal bipyramids that share corners with three equivalent I(1)Rb4Sn square pyramids, corners with four equivalent I(2)Rb2Sn3 trigonal bipyramids, corners with six equivalent I(3)Rb3Sn2 trigonal bipyramids, edges with four equivalent I(1)Rb4Sn square pyramids, edges with two equivalent I(2)Rb2Sn3 trigonal bipyramids, and edges with three equivalent I(3)Rb3Sn2 trigonal bipyramids. In the third I site, I(3) is bonded to three equivalent Rb(1) and two equivalent Sn(1) atoms to form distorted IRb3Sn2 trigonal bipyramids that share corners with six equivalent I(1)Rb4Sn square pyramids, corners with six equivalent I(2)Rb2Sn3 trigonal bipyramids, edges with four equivalent I(1)Rb4Sn square pyramids, edges with three equivalent I(2)Rb2Sn3 trigonal bipyramids, and edges with four equivalent I(3)Rb3Sn2 trigonal bipyramids.
RbSnI3 crystallizes in the orthorhombic Pnma space group. Rb(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 (3.84 Å) and one longer (4.18 Å) Rb(1)-I(2) bond length. There are two shorter (3.85 Å) and one longer (4.00 Å) Rb(1)-I(3) bond length. There are two shorter (3.85 Å) and two longer (3.86 Å) Rb(1)-I(1) bond lengths. Sn(1) is bonded to one I(1), two equivalent I(3), and three equivalent I(2) atoms to form edge-sharing SnI6 octahedra. The Sn(1)-I(1) bond length is 3.00 Å. Both Sn(1)-I(3) bond lengths are 3.21 Å. There are two shorter (3.23 Å) and one longer (3.42 Å) Sn(1)-I(2) bond length. There are three inequivalent I sites. In the first I site, I(1) is bonded to four equivalent Rb(1) and one Sn(1) atom to form distorted IRb4Sn square pyramids that share corners with four equivalent I(1)Rb4Sn square pyramids, corners with three equivalent I(2)Rb2Sn3 trigonal bipyramids, corners with six equivalent I(3)Rb3Sn2 trigonal bipyramids, edges with four equivalent I(1)Rb4Sn square pyramids, edges with four equivalent I(2)Rb2Sn3 trigonal bipyramids, and edges with four equivalent I(3)Rb3Sn2 trigonal bipyramids. In the second I site, I(2) is bonded to two equivalent Rb(1) and three equivalent Sn(1) atoms to form distorted IRb2Sn3 trigonal bipyramids that share corners with three equivalent I(1)Rb4Sn square pyramids, corners with four equivalent I(2)Rb2Sn3 trigonal bipyramids, corners with six equivalent I(3)Rb3Sn2 trigonal bipyramids, edges with four equivalent I(1)Rb4Sn square pyramids, edges with two equivalent I(2)Rb2Sn3 trigonal bipyramids, and edges with three equivalent I(3)Rb3Sn2 trigonal bipyramids. In the third I site, I(3) is bonded to three equivalent Rb(1) and two equivalent Sn(1) atoms to form distorted IRb3Sn2 trigonal bipyramids that share corners with six equivalent I(1)Rb4Sn square pyramids, corners with six equivalent I(2)Rb2Sn3 trigonal bipyramids, edges with four equivalent I(1)Rb4Sn square pyramids, edges with three equivalent I(2)Rb2Sn3 trigonal bipyramids, and edges with four equivalent I(3)Rb3Sn2 trigonal bipyramids.