Au4Hg crystallizes in the trigonal R-3m space group. There are four inequivalent Au sites. In the first Au site, Au(1) is bonded to three equivalent Au(2), six equivalent Au(1), and three equivalent Hg(1) atoms to form distorted AuHg3Au9 cuboctahedra that share corners with three equivalent Au(2)Au12 cuboctahedra; corners with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with six equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine Au(2,2)Au12 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; faces with six equivalent Au(2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with six equivalent Hg(1)Hg6Au6 cuboctahedra. In the second Au site, Au(2) is bonded to three equivalent Au(1) and nine Au(2,2) atoms to form AuAu12 cuboctahedra that share corners with three equivalent Au(1)Hg3Au9 cuboctahedra; corners with three equivalent Hg(1)Hg6Au6 cuboctahedra; corners with six equivalent Au(2)Au12 cuboctahedra; edges with three equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with twelve Au(2,2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with twelve Au(2,2)Au12 cuboctahedra. In the third Au site, Au(2) is bonded to three equivalent Au(1) and nine Au(2,2) atoms to form AuAu12 cuboctahedra that share corners with three equivalent Au(1)Hg3Au9 cuboctahedra; corners with three equivalent Hg(1)Hg6Au6 cuboctahedra; corners with six equivalent Au(2)Au12 cuboctahedra; edges with three equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with twelve Au(2,2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with twelve Au(2,2)Au12 cuboctahedra. In the fourth Au site, Au(2) is bonded to three equivalent Au(1) and nine Au(2,2) atoms to form AuAu12 cuboctahedra that share corners with three equivalent Au(1)Hg3Au9 cuboctahedra; corners with three equivalent Hg(1)Hg6Au6 cuboctahedra; corners with six equivalent Au(2)Au12 cuboctahedra; edges with three equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with twelve Au(2,2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with twelve Au(2,2)Au12 cuboctahedra. Hg(1) is bonded to six equivalent Au(1) and six equivalent Hg(1) atoms to form distorted HgHg6Au6 cuboctahedra that share corners with six equivalent Au(2)Au12 cuboctahedra, corners with six equivalent Hg(1)Hg6Au6 cuboctahedra, edges with six equivalent Au(2)Au12 cuboctahedra, edges with six equivalent Hg(1)Hg6Au6 cuboctahedra, edges with twelve equivalent Au(1)Hg3Au9 cuboctahedra, faces with six equivalent Hg(1)Hg6Au6 cuboctahedra, and faces with twelve equivalent Au(1)Hg3Au9 cuboctahedra.
Au4Hg crystallizes in the trigonal R-3m space group. There are four inequivalent Au sites. In the first Au site, Au(1) is bonded to three equivalent Au(2), six equivalent Au(1), and three equivalent Hg(1) atoms to form distorted AuHg3Au9 cuboctahedra that share corners with three equivalent Au(2)Au12 cuboctahedra; corners with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with six equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine Au(2,2)Au12 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; faces with six equivalent Au(2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with six equivalent Hg(1)Hg6Au6 cuboctahedra. All Au(1)-Au(2) bond lengths are 2.88 Å. All Au(1)-Au(1) bond lengths are 3.01 Å. All Au(1)-Hg(1) bond lengths are 3.03 Å. In the second Au site, Au(2) is bonded to three equivalent Au(1) and nine Au(2,2) atoms to form AuAu12 cuboctahedra that share corners with three equivalent Au(1)Hg3Au9 cuboctahedra; corners with three equivalent Hg(1)Hg6Au6 cuboctahedra; corners with six equivalent Au(2)Au12 cuboctahedra; edges with three equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with twelve Au(2,2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with twelve Au(2,2)Au12 cuboctahedra. There are three shorter (2.86 Å) and six longer (3.01 Å) Au(2)-Au(2,2) bond lengths. In the third Au site, Au(2) is bonded to three equivalent Au(1) and nine Au(2,2) atoms to form AuAu12 cuboctahedra that share corners with three equivalent Au(1)Hg3Au9 cuboctahedra; corners with three equivalent Hg(1)Hg6Au6 cuboctahedra; corners with six equivalent Au(2)Au12 cuboctahedra; edges with three equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with twelve Au(2,2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with twelve Au(2,2)Au12 cuboctahedra. All Au(2)-Au(1) bond lengths are 2.88 Å. All Au(2)-Au(2) bond lengths are 3.01 Å. In the fourth Au site, Au(2) is bonded to three equivalent Au(1) and nine Au(2,2) atoms to form AuAu12 cuboctahedra that share corners with three equivalent Au(1)Hg3Au9 cuboctahedra; corners with three equivalent Hg(1)Hg6Au6 cuboctahedra; corners with six equivalent Au(2)Au12 cuboctahedra; edges with three equivalent Hg(1)Hg6Au6 cuboctahedra; edges with nine equivalent Au(1)Hg3Au9 cuboctahedra; edges with twelve Au(2,2)Au12 cuboctahedra; faces with six equivalent Au(1)Hg3Au9 cuboctahedra; and faces with twelve Au(2,2)Au12 cuboctahedra. All Au(2)-Au(1) bond lengths are 2.88 Å. There are three shorter (2.86 Å) and six longer (3.01 Å) Au(2)-Au(2,2) bond lengths. Hg(1) is bonded to six equivalent Au(1) and six equivalent Hg(1) atoms to form distorted HgHg6Au6 cuboctahedra that share corners with six equivalent Au(2)Au12 cuboctahedra, corners with six equivalent Hg(1)Hg6Au6 cuboctahedra, edges with six equivalent Au(2)Au12 cuboctahedra, edges with six equivalent Hg(1)Hg6Au6 cuboctahedra, edges with twelve equivalent Au(1)Hg3Au9 cuboctahedra, faces with six equivalent Hg(1)Hg6Au6 cuboctahedra, and faces with twelve equivalent Au(1)Hg3Au9 cuboctahedra. All Hg(1)-Hg(1) bond lengths are 3.01 Å.