Ho7PtI12 is trigonal omega-derived structured and crystallizes in the trigonal R-3 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to one Pt(1), two equivalent I(1), and three equivalent I(2) atoms to form distorted HoPtI5 octahedra that share corners with three equivalent Ho(1)PtI5 octahedra,  an edgeedge with one Ho(2)I6 octahedra, and edges with five equivalent Ho(1)PtI5 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the second Ho site, Ho(2) is bonded to six equivalent I(1) atoms to form edge-sharing HoI6 octahedra. Pt(1) is bonded in an octahedral geometry to six equivalent Ho(1) atoms. There are two inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to one Ho(2) and two equivalent Ho(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to three equivalent Ho(1) atoms.
Ho7PtI12 is trigonal omega-derived structured and crystallizes in the trigonal R-3 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to one Pt(1), two equivalent I(1), and three equivalent I(2) atoms to form distorted HoPtI5 octahedra that share corners with three equivalent Ho(1)PtI5 octahedra,  an edgeedge with one Ho(2)I6 octahedra, and edges with five equivalent Ho(1)PtI5 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. The Ho(1)-Pt(1) bond length is 2.69 Å. Both Ho(1)-I(1) bond lengths are 3.15 Å. There are a spread of Ho(1)-I(2) bond distances ranging from 3.09-3.31 Å. In the second Ho site, Ho(2) is bonded to six equivalent I(1) atoms to form edge-sharing HoI6 octahedra. All Ho(2)-I(1) bond lengths are 3.05 Å. Pt(1) is bonded in an octahedral geometry to six equivalent Ho(1) atoms. There are two inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to one Ho(2) and two equivalent Ho(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to three equivalent Ho(1) atoms.