RbCaI3 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 8-coordinate geometry to one I(2), three equivalent I(1), and four equivalent I(3) atoms. Ca(1) is bonded to one I(3), two equivalent I(1), and three equivalent I(2) atoms to form edge-sharing CaI6 octahedra. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 5-coordinate geometry to three equivalent Rb(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1) and three equivalent Ca(1) atoms. In the third I site, I(3) is bonded to four equivalent Rb(1) and one Ca(1) atom to form a mixture of distorted corner and edge-sharing IRb4Ca square pyramids.
RbCaI3 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 8-coordinate geometry to one I(2), three equivalent I(1), and four equivalent I(3) atoms. The Rb(1)-I(2) bond length is 3.95 Å. There are two shorter (3.87 Å) and one longer (4.05 Å) Rb(1)-I(1) bond length. All Rb(1)-I(3) bond lengths are 3.81 Å. Ca(1) is bonded to one I(3), two equivalent I(1), and three equivalent I(2) atoms to form edge-sharing CaI6 octahedra. The Ca(1)-I(3) bond length is 3.06 Å. Both Ca(1)-I(1) bond lengths are 3.15 Å. There is one shorter (3.18 Å) and two longer (3.19 Å) Ca(1)-I(2) bond lengths. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 5-coordinate geometry to three equivalent Rb(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1) and three equivalent Ca(1) atoms. In the third I site, I(3) is bonded to four equivalent Rb(1) and one Ca(1) atom to form a mixture of distorted corner and edge-sharing IRb4Ca square pyramids.