UHg3 is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. U(1) is bonded to six equivalent U(1) and six equivalent Hg(2) atoms to form UU6Hg6 cuboctahedra that share corners with six equivalent U(1)U6Hg6 cuboctahedra, corners with twelve equivalent Hg(1)Hg12 cuboctahedra, edges with six equivalent U(1)U6Hg6 cuboctahedra, edges with twelve equivalent Hg(2)U3Hg9 cuboctahedra, faces with two equivalent Hg(1)Hg12 cuboctahedra, faces with six equivalent U(1)U6Hg6 cuboctahedra, and faces with twelve equivalent Hg(2)U3Hg9 cuboctahedra. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to six equivalent Hg(1) and six equivalent Hg(2) atoms to form HgHg12 cuboctahedra that share corners with six equivalent Hg(1)Hg12 cuboctahedra, corners with twelve equivalent U(1)U6Hg6 cuboctahedra, edges with six equivalent Hg(1)Hg12 cuboctahedra, edges with twelve equivalent Hg(2)U3Hg9 cuboctahedra, faces with two equivalent U(1)U6Hg6 cuboctahedra, faces with six equivalent Hg(1)Hg12 cuboctahedra, and faces with twelve equivalent Hg(2)U3Hg9 cuboctahedra. In the second Hg site, Hg(2) is bonded to three equivalent U(1), three equivalent Hg(1), and six equivalent Hg(2) atoms to form distorted HgU3Hg9 cuboctahedra that share corners with eighteen equivalent Hg(2)U3Hg9 cuboctahedra, edges with six equivalent U(1)U6Hg6 cuboctahedra, edges with six equivalent Hg(1)Hg12 cuboctahedra, edges with six equivalent Hg(2)U3Hg9 cuboctahedra, faces with six equivalent U(1)U6Hg6 cuboctahedra, faces with six equivalent Hg(1)Hg12 cuboctahedra, and faces with eight equivalent Hg(2)U3Hg9 cuboctahedra.
UHg3 is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. U(1) is bonded to six equivalent U(1) and six equivalent Hg(2) atoms to form UU6Hg6 cuboctahedra that share corners with six equivalent U(1)U6Hg6 cuboctahedra, corners with twelve equivalent Hg(1)Hg12 cuboctahedra, edges with six equivalent U(1)U6Hg6 cuboctahedra, edges with twelve equivalent Hg(2)U3Hg9 cuboctahedra, faces with two equivalent Hg(1)Hg12 cuboctahedra, faces with six equivalent U(1)U6Hg6 cuboctahedra, and faces with twelve equivalent Hg(2)U3Hg9 cuboctahedra. All U(1)-U(1) bond lengths are 3.17 Å. All U(1)-Hg(2) bond lengths are 3.30 Å. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to six equivalent Hg(1) and six equivalent Hg(2) atoms to form HgHg12 cuboctahedra that share corners with six equivalent Hg(1)Hg12 cuboctahedra, corners with twelve equivalent U(1)U6Hg6 cuboctahedra, edges with six equivalent Hg(1)Hg12 cuboctahedra, edges with twelve equivalent Hg(2)U3Hg9 cuboctahedra, faces with two equivalent U(1)U6Hg6 cuboctahedra, faces with six equivalent Hg(1)Hg12 cuboctahedra, and faces with twelve equivalent Hg(2)U3Hg9 cuboctahedra. All Hg(1)-Hg(1) bond lengths are 3.17 Å. All Hg(1)-Hg(2) bond lengths are 3.26 Å. In the second Hg site, Hg(2) is bonded to three equivalent U(1), three equivalent Hg(1), and six equivalent Hg(2) atoms to form distorted HgU3Hg9 cuboctahedra that share corners with eighteen equivalent Hg(2)U3Hg9 cuboctahedra, edges with six equivalent U(1)U6Hg6 cuboctahedra, edges with six equivalent Hg(1)Hg12 cuboctahedra, edges with six equivalent Hg(2)U3Hg9 cuboctahedra, faces with six equivalent U(1)U6Hg6 cuboctahedra, faces with six equivalent Hg(1)Hg12 cuboctahedra, and faces with eight equivalent Hg(2)U3Hg9 cuboctahedra. All Hg(2)-Hg(2) bond lengths are 3.17 Å.