BaCaI4 crystallizes in the orthorhombic Cmc2_1 space group. Ba(1) is bonded in a 9-coordinate geometry to one I(1), two equivalent I(2), three equivalent I(3), and three equivalent I(4) atoms. Ca(1) is bonded to one I(3), one I(4), two equivalent I(1), and two equivalent I(2) atoms to form corner-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 10-46°. There are four inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1) and two equivalent Ca(1) atoms. In the third I site, I(3) is bonded in a 4-coordinate geometry to three equivalent Ba(1) and one Ca(1) atom. In the fourth I site, I(4) is bonded to three equivalent Ba(1) and one Ca(1) atom to form corner-sharing IBa3Ca trigonal pyramids.
BaCaI4 crystallizes in the orthorhombic Cmc2_1 space group. Ba(1) is bonded in a 9-coordinate geometry to one I(1), two equivalent I(2), three equivalent I(3), and three equivalent I(4) atoms. The Ba(1)-I(1) bond length is 3.58 Å. Both Ba(1)-I(2) bond lengths are 4.11 Å. There are two shorter (3.78 Å) and one longer (4.18 Å) Ba(1)-I(3) bond length. There is one shorter (3.64 Å) and two longer (3.69 Å) Ba(1)-I(4) bond lengths. Ca(1) is bonded to one I(3), one I(4), two equivalent I(1), and two equivalent I(2) atoms to form corner-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 10-46°. The Ca(1)-I(3) bond length is 3.10 Å. The Ca(1)-I(4) bond length is 3.18 Å. Both Ca(1)-I(1) bond lengths are 3.05 Å. There is one shorter (3.12 Å) and one longer (3.17 Å) Ca(1)-I(2) bond length. There are four inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1) and two equivalent Ca(1) atoms. In the third I site, I(3) is bonded in a 4-coordinate geometry to three equivalent Ba(1) and one Ca(1) atom. In the fourth I site, I(4) is bonded to three equivalent Ba(1) and one Ca(1) atom to form corner-sharing IBa3Ca trigonal pyramids.