Cs2PtSb2 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 6-coordinate geometry to six equivalent Sb(1) atoms. In the second Cs site, Cs(2) is bonded in a 4-coordinate geometry to two equivalent Pt(1) and six equivalent Sb(1) atoms. Pt(1) is bonded to two equivalent Cs(2) and four equivalent Sb(1) atoms to form distorted face-sharing PtCs2Sb4 octahedra. Sb(1) is bonded in a 9-coordinate geometry to three equivalent Cs(1), three equivalent Cs(2), two equivalent Pt(1), and one Sb(1) atom.
Cs2PtSb2 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 6-coordinate geometry to six equivalent Sb(1) atoms. There are two shorter (3.85 Å) and four longer (4.26 Å) Cs(1)-Sb(1) bond lengths. In the second Cs site, Cs(2) is bonded in a 4-coordinate geometry to two equivalent Pt(1) and six equivalent Sb(1) atoms. Both Cs(2)-Pt(1) bond lengths are 3.45 Å. There are two shorter (3.93 Å) and four longer (4.07 Å) Cs(2)-Sb(1) bond lengths. Pt(1) is bonded to two equivalent Cs(2) and four equivalent Sb(1) atoms to form distorted face-sharing PtCs2Sb4 octahedra. All Pt(1)-Sb(1) bond lengths are 2.67 Å. Sb(1) is bonded in a 9-coordinate geometry to three equivalent Cs(1), three equivalent Cs(2), two equivalent Pt(1), and one Sb(1) atom. The Sb(1)-Sb(1) bond length is 2.81 Å.