LuCoGa5 crystallizes in the tetragonal P4/mmm space group. Lu(1) is bonded to four equivalent Ga(2) and eight Ga(1,1) atoms to form LuGa12 cuboctahedra that share corners with four equivalent Lu(1)Ga12 cuboctahedra, faces with four equivalent Lu(1)Ga12 cuboctahedra, and faces with four equivalent Ga(2)Lu4Ga8 cuboctahedra. Co(1) is bonded in a body-centered cubic geometry to eight Ga(1,1) atoms. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 11-coordinate geometry to two equivalent Lu(1); two equivalent Co(1); two equivalent Ga(2); and five Ga(1,1) atoms. In the second Ga site, Ga(1) is bonded in a 11-coordinate geometry to two equivalent Lu(1); two equivalent Co(1); two equivalent Ga(2); and five Ga(1,1) atoms. In the third Ga site, Ga(2) is bonded to four equivalent Lu(1) and eight Ga(1,1) atoms to form distorted GaLu4Ga8 cuboctahedra that share corners with four equivalent Ga(2)Lu4Ga8 cuboctahedra, faces with four equivalent Lu(1)Ga12 cuboctahedra, and faces with four equivalent Ga(2)Lu4Ga8 cuboctahedra.
LuCoGa5 crystallizes in the tetragonal P4/mmm space group. Lu(1) is bonded to four equivalent Ga(2) and eight Ga(1,1) atoms to form LuGa12 cuboctahedra that share corners with four equivalent Lu(1)Ga12 cuboctahedra, faces with four equivalent Lu(1)Ga12 cuboctahedra, and faces with four equivalent Ga(2)Lu4Ga8 cuboctahedra. All Lu(1)-Ga(2) bond lengths are 2.97 Å. All Lu(1)-Ga(1,1) bond lengths are 2.96 Å. Co(1) is bonded in a body-centered cubic geometry to eight Ga(1,1) atoms. All Co(1)-Ga(1,1) bond lengths are 2.47 Å. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 11-coordinate geometry to two equivalent Lu(1); two equivalent Co(1); two equivalent Ga(2); and five Ga(1,1) atoms. Both Ga(1)-Ga(2) bond lengths are 2.96 Å. There is one shorter (2.60 Å) and four longer (2.97 Å) Ga(1)-Ga(1,1) bond lengths. In the second Ga site, Ga(1) is bonded in a 11-coordinate geometry to two equivalent Lu(1); two equivalent Co(1); two equivalent Ga(2); and five Ga(1,1) atoms. Both Ga(1)-Ga(2) bond lengths are 2.96 Å. All Ga(1)-Ga(1) bond lengths are 2.97 Å. In the third Ga site, Ga(2) is bonded to four equivalent Lu(1) and eight Ga(1,1) atoms to form distorted GaLu4Ga8 cuboctahedra that share corners with four equivalent Ga(2)Lu4Ga8 cuboctahedra, faces with four equivalent Lu(1)Ga12 cuboctahedra, and faces with four equivalent Ga(2)Lu4Ga8 cuboctahedra.