Pt3Hg crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded to four equivalent Pt(1), four equivalent Pt(2), and four equivalent Hg(1) atoms to form PtHg4Pt8 cuboctahedra that share corners with twelve equivalent Pt(1)Hg4Pt8 cuboctahedra, edges with eight equivalent Pt(1)Hg4Pt8 cuboctahedra, edges with eight equivalent Pt(2)Pt12 cuboctahedra, edges with eight equivalent Hg(1)Hg4Pt8 cuboctahedra, faces with four equivalent Pt(2)Pt12 cuboctahedra, faces with four equivalent Hg(1)Hg4Pt8 cuboctahedra, and faces with ten equivalent Pt(1)Hg4Pt8 cuboctahedra. In the second Pt site, Pt(2) is bonded to four equivalent Pt(2) and eight equivalent Pt(1) atoms to form PtPt12 cuboctahedra that share corners with four equivalent Pt(2)Pt12 cuboctahedra, corners with eight equivalent Hg(1)Hg4Pt8 cuboctahedra, edges with eight equivalent Hg(1)Hg4Pt8 cuboctahedra, edges with sixteen equivalent Pt(1)Hg4Pt8 cuboctahedra, faces with two equivalent Hg(1)Hg4Pt8 cuboctahedra, faces with eight equivalent Pt(1)Hg4Pt8 cuboctahedra, and faces with eight equivalent Pt(2)Pt12 cuboctahedra. Hg(1) is bonded to eight equivalent Pt(1) and four equivalent Hg(1) atoms to form HgHg4Pt8 cuboctahedra that share corners with four equivalent Hg(1)Hg4Pt8 cuboctahedra, corners with eight equivalent Pt(2)Pt12 cuboctahedra, edges with eight equivalent Pt(2)Pt12 cuboctahedra, edges with sixteen equivalent Pt(1)Hg4Pt8 cuboctahedra, faces with two equivalent Pt(2)Pt12 cuboctahedra, faces with eight equivalent Pt(1)Hg4Pt8 cuboctahedra, and faces with eight equivalent Hg(1)Hg4Pt8 cuboctahedra.
Pt3Hg crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded to four equivalent Pt(1), four equivalent Pt(2), and four equivalent Hg(1) atoms to form PtHg4Pt8 cuboctahedra that share corners with twelve equivalent Pt(1)Hg4Pt8 cuboctahedra, edges with eight equivalent Pt(1)Hg4Pt8 cuboctahedra, edges with eight equivalent Pt(2)Pt12 cuboctahedra, edges with eight equivalent Hg(1)Hg4Pt8 cuboctahedra, faces with four equivalent Pt(2)Pt12 cuboctahedra, faces with four equivalent Hg(1)Hg4Pt8 cuboctahedra, and faces with ten equivalent Pt(1)Hg4Pt8 cuboctahedra. All Pt(1)-Pt(1) bond lengths are 2.93 Å. All Pt(1)-Pt(2) bond lengths are 2.79 Å. All Pt(1)-Hg(1) bond lengths are 2.94 Å. In the second Pt site, Pt(2) is bonded to four equivalent Pt(2) and eight equivalent Pt(1) atoms to form PtPt12 cuboctahedra that share corners with four equivalent Pt(2)Pt12 cuboctahedra, corners with eight equivalent Hg(1)Hg4Pt8 cuboctahedra, edges with eight equivalent Hg(1)Hg4Pt8 cuboctahedra, edges with sixteen equivalent Pt(1)Hg4Pt8 cuboctahedra, faces with two equivalent Hg(1)Hg4Pt8 cuboctahedra, faces with eight equivalent Pt(1)Hg4Pt8 cuboctahedra, and faces with eight equivalent Pt(2)Pt12 cuboctahedra. All Pt(2)-Pt(2) bond lengths are 2.93 Å. Hg(1) is bonded to eight equivalent Pt(1) and four equivalent Hg(1) atoms to form HgHg4Pt8 cuboctahedra that share corners with four equivalent Hg(1)Hg4Pt8 cuboctahedra, corners with eight equivalent Pt(2)Pt12 cuboctahedra, edges with eight equivalent Pt(2)Pt12 cuboctahedra, edges with sixteen equivalent Pt(1)Hg4Pt8 cuboctahedra, faces with two equivalent Pt(2)Pt12 cuboctahedra, faces with eight equivalent Pt(1)Hg4Pt8 cuboctahedra, and faces with eight equivalent Hg(1)Hg4Pt8 cuboctahedra. All Hg(1)-Hg(1) bond lengths are 2.93 Å.