SrCaI4 crystallizes in the monoclinic P2_1/c space group. Sr(1) is bonded to one I(1), one I(4), two equivalent I(2), and two equivalent I(3) atoms to form distorted SrI6 pentagonal pyramids that share corners with two equivalent Sr(1)I6 pentagonal pyramids,  an edgeedge with one Sr(1)I6 pentagonal pyramid, and edges with four equivalent Ca(1)I6 pentagonal pyramids. Ca(1) is bonded to one I(2), one I(3), two equivalent I(1), and two equivalent I(4) atoms to form distorted CaI6 pentagonal pyramids that share corners with two equivalent Ca(1)I6 pentagonal pyramids,  an edgeedge with one Ca(1)I6 pentagonal pyramid, and edges with four equivalent Sr(1)I6 pentagonal pyramids. There are four inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to one Sr(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to two equivalent Sr(1) and one Ca(1) atom. In the third I site, I(3) is bonded in a trigonal non-coplanar geometry to two equivalent Sr(1) and one Ca(1) atom. In the fourth I site, I(4) is bonded in a distorted T-shaped geometry to one Sr(1) and two equivalent Ca(1) atoms.
SrCaI4 crystallizes in the monoclinic P2_1/c space group. Sr(1) is bonded to one I(1), one I(4), two equivalent I(2), and two equivalent I(3) atoms to form distorted SrI6 pentagonal pyramids that share corners with two equivalent Sr(1)I6 pentagonal pyramids,  an edgeedge with one Sr(1)I6 pentagonal pyramid, and edges with four equivalent Ca(1)I6 pentagonal pyramids. The Sr(1)-I(1) bond length is 3.33 Å. The Sr(1)-I(4) bond length is 3.33 Å. There is one shorter (3.31 Å) and one longer (3.32 Å) Sr(1)-I(2) bond length. There is one shorter (3.28 Å) and one longer (3.36 Å) Sr(1)-I(3) bond length. Ca(1) is bonded to one I(2), one I(3), two equivalent I(1), and two equivalent I(4) atoms to form distorted CaI6 pentagonal pyramids that share corners with two equivalent Ca(1)I6 pentagonal pyramids,  an edgeedge with one Ca(1)I6 pentagonal pyramid, and edges with four equivalent Sr(1)I6 pentagonal pyramids. The Ca(1)-I(2) bond length is 3.21 Å. The Ca(1)-I(3) bond length is 3.18 Å. There is one shorter (3.23 Å) and one longer (3.25 Å) Ca(1)-I(1) bond length. There is one shorter (3.21 Å) and one longer (3.22 Å) Ca(1)-I(4) bond length. There are four inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to one Sr(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to two equivalent Sr(1) and one Ca(1) atom. In the third I site, I(3) is bonded in a trigonal non-coplanar geometry to two equivalent Sr(1) and one Ca(1) atom. In the fourth I site, I(4) is bonded in a distorted T-shaped geometry to one Sr(1) and two equivalent Ca(1) atoms.