BaSr2I6 crystallizes in the monoclinic C2/c space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent I(1), two equivalent I(2), and four equivalent I(3) atoms. Sr(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form distorted edge-sharing SrI6 pentagonal pyramids. There are three inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Sr(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to one Ba(1) and two equivalent Sr(1) atoms. In the third I site, I(3) is bonded to two equivalent Ba(1) and two equivalent Sr(1) atoms to form a mixture of distorted corner and edge-sharing IBa2Sr2 trigonal pyramids.
BaSr2I6 crystallizes in the monoclinic C2/c space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent I(1), two equivalent I(2), and four equivalent I(3) atoms. Both Ba(1)-I(1) bond lengths are 3.50 Å. Both Ba(1)-I(2) bond lengths are 3.54 Å. There are two shorter (3.76 Å) and two longer (3.83 Å) Ba(1)-I(3) bond lengths. Sr(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form distorted edge-sharing SrI6 pentagonal pyramids. There is one shorter (3.26 Å) and one longer (3.32 Å) Sr(1)-I(1) bond length. There is one shorter (3.30 Å) and one longer (3.35 Å) Sr(1)-I(2) bond length. There is one shorter (3.35 Å) and one longer (3.38 Å) Sr(1)-I(3) bond length. There are three inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to one Ba(1) and two equivalent Sr(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to one Ba(1) and two equivalent Sr(1) atoms. In the third I site, I(3) is bonded to two equivalent Ba(1) and two equivalent Sr(1) atoms to form a mixture of distorted corner and edge-sharing IBa2Sr2 trigonal pyramids.