Pr4RuI5 crystallizes in the monoclinic C2/m space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 6-coordinate geometry to one Ru(1), two equivalent I(3), and three equivalent I(2) atoms. In the second Pr site, Pr(2) is bonded to two equivalent Ru(1), one I(2), one I(3), and two equivalent I(1) atoms to form a mixture of corner and edge-sharing PrRu2I4 octahedra. The corner-sharing octahedra are not tilted. Ru(1) is bonded to two equivalent Pr(1) and four equivalent Pr(2) atoms to form edge-sharing RuPr6 octahedra. There are three inequivalent I sites. In the first I site, I(1) is bonded in a square co-planar geometry to four equivalent Pr(2) atoms. In the second I site, I(2) is bonded in a distorted see-saw-like geometry to one Pr(2) and three equivalent Pr(1) atoms. In the third I site, I(3) is bonded in a distorted T-shaped geometry to one Pr(2) and two equivalent Pr(1) atoms.
Pr4RuI5 crystallizes in the monoclinic C2/m space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 6-coordinate geometry to one Ru(1), two equivalent I(3), and three equivalent I(2) atoms. The Pr(1)-Ru(1) bond length is 2.66 Å. Both Pr(1)-I(3) bond lengths are 3.26 Å. There are two shorter (3.30 Å) and one longer (3.57 Å) Pr(1)-I(2) bond length. In the second Pr site, Pr(2) is bonded to two equivalent Ru(1), one I(2), one I(3), and two equivalent I(1) atoms to form a mixture of corner and edge-sharing PrRu2I4 octahedra. The corner-sharing octahedra are not tilted. Both Pr(2)-Ru(1) bond lengths are 2.94 Å. The Pr(2)-I(2) bond length is 3.32 Å. The Pr(2)-I(3) bond length is 3.25 Å. Both Pr(2)-I(1) bond lengths are 3.44 Å. Ru(1) is bonded to two equivalent Pr(1) and four equivalent Pr(2) atoms to form edge-sharing RuPr6 octahedra. There are three inequivalent I sites. In the first I site, I(1) is bonded in a square co-planar geometry to four equivalent Pr(2) atoms. In the second I site, I(2) is bonded in a distorted see-saw-like geometry to one Pr(2) and three equivalent Pr(1) atoms. In the third I site, I(3) is bonded in a distorted T-shaped geometry to one Pr(2) and two equivalent Pr(1) atoms.