Sr3Sm is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Sr(1) is bonded to eight equivalent Sr(1) and four equivalent Sm(1) atoms to form distorted SrSr8Sm4 cuboctahedra that share corners with four equivalent Sm(1)Sr12 cuboctahedra, corners with fourteen equivalent Sr(1)Sr8Sm4 cuboctahedra, edges with six equivalent Sm(1)Sr12 cuboctahedra, edges with twelve equivalent Sr(1)Sr8Sm4 cuboctahedra, faces with four equivalent Sm(1)Sr12 cuboctahedra, and faces with sixteen equivalent Sr(1)Sr8Sm4 cuboctahedra. Sm(1) is bonded to twelve equivalent Sr(1) atoms to form SmSr12 cuboctahedra that share corners with six equivalent Sm(1)Sr12 cuboctahedra, corners with twelve equivalent Sr(1)Sr8Sm4 cuboctahedra, edges with eighteen equivalent Sr(1)Sr8Sm4 cuboctahedra, faces with eight equivalent Sm(1)Sr12 cuboctahedra, and faces with twelve equivalent Sr(1)Sr8Sm4 cuboctahedra.
Sr3Sm is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Sr(1) is bonded to eight equivalent Sr(1) and four equivalent Sm(1) atoms to form distorted SrSr8Sm4 cuboctahedra that share corners with four equivalent Sm(1)Sr12 cuboctahedra, corners with fourteen equivalent Sr(1)Sr8Sm4 cuboctahedra, edges with six equivalent Sm(1)Sr12 cuboctahedra, edges with twelve equivalent Sr(1)Sr8Sm4 cuboctahedra, faces with four equivalent Sm(1)Sr12 cuboctahedra, and faces with sixteen equivalent Sr(1)Sr8Sm4 cuboctahedra. There are a spread of Sr(1)-Sr(1) bond distances ranging from 3.96-4.22 Å. There are two shorter (3.99 Å) and two longer (4.09 Å) Sr(1)-Sm(1) bond lengths. Sm(1) is bonded to twelve equivalent Sr(1) atoms to form SmSr12 cuboctahedra that share corners with six equivalent Sm(1)Sr12 cuboctahedra, corners with twelve equivalent Sr(1)Sr8Sm4 cuboctahedra, edges with eighteen equivalent Sr(1)Sr8Sm4 cuboctahedra, faces with eight equivalent Sm(1)Sr12 cuboctahedra, and faces with twelve equivalent Sr(1)Sr8Sm4 cuboctahedra.