LuEu3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Lu(1) is bonded to twelve equivalent Eu(1) atoms to form LuEu12 cuboctahedra that share corners with six equivalent Lu(1)Eu12 cuboctahedra, corners with twelve equivalent Eu(1)Eu8Lu4 cuboctahedra, edges with eighteen equivalent Eu(1)Eu8Lu4 cuboctahedra, faces with eight equivalent Lu(1)Eu12 cuboctahedra, and faces with twelve equivalent Eu(1)Eu8Lu4 cuboctahedra. Eu(1) is bonded to four equivalent Lu(1) and eight equivalent Eu(1) atoms to form EuEu8Lu4 cuboctahedra that share corners with four equivalent Lu(1)Eu12 cuboctahedra, corners with fourteen equivalent Eu(1)Eu8Lu4 cuboctahedra, edges with six equivalent Lu(1)Eu12 cuboctahedra, edges with twelve equivalent Eu(1)Eu8Lu4 cuboctahedra, faces with four equivalent Lu(1)Eu12 cuboctahedra, and faces with sixteen equivalent Eu(1)Eu8Lu4 cuboctahedra.
LuEu3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Lu(1) is bonded to twelve equivalent Eu(1) atoms to form LuEu12 cuboctahedra that share corners with six equivalent Lu(1)Eu12 cuboctahedra, corners with twelve equivalent Eu(1)Eu8Lu4 cuboctahedra, edges with eighteen equivalent Eu(1)Eu8Lu4 cuboctahedra, faces with eight equivalent Lu(1)Eu12 cuboctahedra, and faces with twelve equivalent Eu(1)Eu8Lu4 cuboctahedra. There are six shorter (3.72 Å) and six longer (3.80 Å) Lu(1)-Eu(1) bond lengths. Eu(1) is bonded to four equivalent Lu(1) and eight equivalent Eu(1) atoms to form EuEu8Lu4 cuboctahedra that share corners with four equivalent Lu(1)Eu12 cuboctahedra, corners with fourteen equivalent Eu(1)Eu8Lu4 cuboctahedra, edges with six equivalent Lu(1)Eu12 cuboctahedra, edges with twelve equivalent Eu(1)Eu8Lu4 cuboctahedra, faces with four equivalent Lu(1)Eu12 cuboctahedra, and faces with sixteen equivalent Eu(1)Eu8Lu4 cuboctahedra. There are a spread of Eu(1)-Eu(1) bond distances ranging from 3.72-3.87 Å.