PtI3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form a mixture of edge and corner-sharing PtI6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Pt site, Pt(2) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form a mixture of edge and corner-sharing PtI6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a linear geometry to one Pt(1) and one Pt(2) atom. In the second I site, I(2) is bonded in an L-shaped geometry to one Pt(1) and one Pt(2) atom. In the third I site, I(3) is bonded in an L-shaped geometry to one Pt(1) and one Pt(2) atom.
PtI3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form a mixture of edge and corner-sharing PtI6 octahedra. The corner-sharing octahedral tilt angles are 4°. Both Pt(1)-I(1) bond lengths are 2.69 Å. Both Pt(1)-I(2) bond lengths are 2.77 Å. Both Pt(1)-I(3) bond lengths are 2.67 Å. In the second Pt site, Pt(2) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form a mixture of edge and corner-sharing PtI6 octahedra. The corner-sharing octahedral tilt angles are 4°. Both Pt(2)-I(1) bond lengths are 3.19 Å. Both Pt(2)-I(2) bond lengths are 2.63 Å. Both Pt(2)-I(3) bond lengths are 2.63 Å. There are three inequivalent I sites. In the first I site, I(1) is bonded in a linear geometry to one Pt(1) and one Pt(2) atom. In the second I site, I(2) is bonded in an L-shaped geometry to one Pt(1) and one Pt(2) atom. In the third I site, I(3) is bonded in an L-shaped geometry to one Pt(1) and one Pt(2) atom.