SmCo2Ga is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the trigonal P-3m1 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 12-coordinate geometry to three equivalent Co(4) and nine equivalent Ga(1) atoms. In the second Sm site, Sm(2) is bonded in a 12-coordinate geometry to three equivalent Co(3) and nine equivalent Co(5) atoms. In the third Sm site, Sm(3) is bonded in a 18-coordinate geometry to three equivalent Co(1), three equivalent Co(2), six equivalent Co(5), and six equivalent Ga(1) atoms. There are five inequivalent Co sites. In the first Co site, Co(1) is bonded in a 9-coordinate geometry to three equivalent Sm(3), three equivalent Co(5), and three equivalent Ga(1) atoms. In the second Co site, Co(2) is bonded in a 9-coordinate geometry to three equivalent Sm(3), three equivalent Co(5), and three equivalent Ga(1) atoms. In the third Co site, Co(3) is bonded to six equivalent Sm(2) and six equivalent Co(5) atoms to form CoSm6Co6 cuboctahedra that share corners with twelve equivalent Co(5)Sm5Co7 cuboctahedra, edges with six equivalent Co(3)Sm6Co6 cuboctahedra, and faces with eighteen equivalent Co(5)Sm5Co7 cuboctahedra. In the fourth Co site, Co(4) is bonded to six equivalent Sm(1) and six equivalent Ga(1) atoms to form CoSm6Ga6 cuboctahedra that share corners with twelve equivalent Ga(1)Sm5Ga4Co3 cuboctahedra, edges with six equivalent Co(4)Sm6Ga6 cuboctahedra, and faces with eighteen equivalent Ga(1)Sm5Ga4Co3 cuboctahedra. In the fifth Co site, Co(5) is bonded to two equivalent Sm(3), three equivalent Sm(2), one Co(1), one Co(2), one Co(3), and four equivalent Co(5) atoms to form CoSm5Co7 cuboctahedra that share corners with two equivalent Co(3)Sm6Co6 cuboctahedra, corners with six equivalent Ga(1)Sm5Ga4Co3 cuboctahedra, corners with nine equivalent Co(5)Sm5Co7 cuboctahedra, edges with four equivalent Co(5)Sm5Co7 cuboctahedra, edges with four equivalent Ga(1)Sm5Ga4Co3 cuboctahedra,  a faceface with one Ga(1)Sm5Ga4Co3 cuboctahedra, faces with three equivalent Co(3)Sm6Co6 cuboctahedra, and faces with ten equivalent Co(5)Sm5Co7 cuboctahedra. Ga(1) is bonded to two equivalent Sm(3), three equivalent Sm(1), one Co(1), one Co(2), one Co(4), and four equivalent Ga(1) atoms to form GaSm5Ga4Co3 cuboctahedra that share corners with two equivalent Co(4)Sm6Ga6 cuboctahedra, corners with six equivalent Co(5)Sm5Co7 cuboctahedra, corners with nine equivalent Ga(1)Sm5Ga4Co3 cuboctahedra, edges with four equivalent Co(5)Sm5Co7 cuboctahedra, edges with four equivalent Ga(1)Sm5Ga4Co3 cuboctahedra,  a faceface with one Co(5)Sm5Co7 cuboctahedra, faces with three equivalent Co(4)Sm6Ga6 cuboctahedra, and faces with ten equivalent Ga(1)Sm5Ga4Co3 cuboctahedra.
SmCo2Ga is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the trigonal P-3m1 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 12-coordinate geometry to three equivalent Co(4) and nine equivalent Ga(1) atoms. All Sm(1)-Co(4) bond lengths are 3.08 Å. All Sm(1)-Ga(1) bond lengths are 3.14 Å. In the second Sm site, Sm(2) is bonded in a 12-coordinate geometry to three equivalent Co(3) and nine equivalent Co(5) atoms. All Sm(2)-Co(3) bond lengths are 3.10 Å. There are six shorter (2.99 Å) and three longer (3.11 Å) Sm(2)-Co(5) bond lengths. In the third Sm site, Sm(3) is bonded in a 18-coordinate geometry to three equivalent Co(1), three equivalent Co(2), six equivalent Co(5), and six equivalent Ga(1) atoms. All Sm(3)-Co(1) bond lengths are 3.04 Å. All Sm(3)-Co(2) bond lengths are 3.04 Å. All Sm(3)-Co(5) bond lengths are 3.28 Å. All Sm(3)-Ga(1) bond lengths are 3.30 Å. There are five inequivalent Co sites. In the first Co site, Co(1) is bonded in a 9-coordinate geometry to three equivalent Sm(3), three equivalent Co(5), and three equivalent Ga(1) atoms. All Co(1)-Co(5) bond lengths are 2.39 Å. All Co(1)-Ga(1) bond lengths are 2.62 Å. In the second Co site, Co(2) is bonded in a 9-coordinate geometry to three equivalent Sm(3), three equivalent Co(5), and three equivalent Ga(1) atoms. All Co(2)-Co(5) bond lengths are 2.40 Å. All Co(2)-Ga(1) bond lengths are 2.54 Å. In the third Co site, Co(3) is bonded to six equivalent Sm(2) and six equivalent Co(5) atoms to form CoSm6Co6 cuboctahedra that share corners with twelve equivalent Co(5)Sm5Co7 cuboctahedra, edges with six equivalent Co(3)Sm6Co6 cuboctahedra, and faces with eighteen equivalent Co(5)Sm5Co7 cuboctahedra. All Co(3)-Co(5) bond lengths are 2.54 Å. In the fourth Co site, Co(4) is bonded to six equivalent Sm(1) and six equivalent Ga(1) atoms to form CoSm6Ga6 cuboctahedra that share corners with twelve equivalent Ga(1)Sm5Ga4Co3 cuboctahedra, edges with six equivalent Co(4)Sm6Ga6 cuboctahedra, and faces with eighteen equivalent Ga(1)Sm5Ga4Co3 cuboctahedra. All Co(4)-Ga(1) bond lengths are 2.69 Å. In the fifth Co site, Co(5) is bonded to two equivalent Sm(3), three equivalent Sm(2), one Co(1), one Co(2), one Co(3), and four equivalent Co(5) atoms to form CoSm5Co7 cuboctahedra that share corners with two equivalent Co(3)Sm6Co6 cuboctahedra, corners with six equivalent Ga(1)Sm5Ga4Co3 cuboctahedra, corners with nine equivalent Co(5)Sm5Co7 cuboctahedra, edges with four equivalent Co(5)Sm5Co7 cuboctahedra, edges with four equivalent Ga(1)Sm5Ga4Co3 cuboctahedra,  a faceface with one Ga(1)Sm5Ga4Co3 cuboctahedra, faces with three equivalent Co(3)Sm6Co6 cuboctahedra, and faces with ten equivalent Co(5)Sm5Co7 cuboctahedra. There are two shorter (2.56 Å) and two longer (2.70 Å) Co(5)-Co(5) bond lengths. Ga(1) is bonded to two equivalent Sm(3), three equivalent Sm(1), one Co(1), one Co(2), one Co(4), and four equivalent Ga(1) atoms to form GaSm5Ga4Co3 cuboctahedra that share corners with two equivalent Co(4)Sm6Ga6 cuboctahedra, corners with six equivalent Co(5)Sm5Co7 cuboctahedra, corners with nine equivalent Ga(1)Sm5Ga4Co3 cuboctahedra, edges with four equivalent Co(5)Sm5Co7 cuboctahedra, edges with four equivalent Ga(1)Sm5Ga4Co3 cuboctahedra,  a faceface with one Co(5)Sm5Co7 cuboctahedra, faces with three equivalent Co(4)Sm6Ga6 cuboctahedra, and faces with ten equivalent Ga(1)Sm5Ga4Co3 cuboctahedra. There are two shorter (2.62 Å) and two longer (2.65 Å) Ga(1)-Ga(1) bond lengths.