Sr3Tb 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 Tb(1) atoms to form SrSr8Tb4 cuboctahedra that share corners with four equivalent Tb(1)Sr12 cuboctahedra, corners with fourteen equivalent Sr(1)Sr8Tb4 cuboctahedra, edges with six equivalent Tb(1)Sr12 cuboctahedra, edges with twelve equivalent Sr(1)Sr8Tb4 cuboctahedra, faces with four equivalent Tb(1)Sr12 cuboctahedra, and faces with sixteen equivalent Sr(1)Sr8Tb4 cuboctahedra. Tb(1) is bonded to twelve equivalent Sr(1) atoms to form TbSr12 cuboctahedra that share corners with six equivalent Tb(1)Sr12 cuboctahedra, corners with twelve equivalent Sr(1)Sr8Tb4 cuboctahedra, edges with eighteen equivalent Sr(1)Sr8Tb4 cuboctahedra, faces with eight equivalent Tb(1)Sr12 cuboctahedra, and faces with twelve equivalent Sr(1)Sr8Tb4 cuboctahedra.
Sr3Tb 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 Tb(1) atoms to form SrSr8Tb4 cuboctahedra that share corners with four equivalent Tb(1)Sr12 cuboctahedra, corners with fourteen equivalent Sr(1)Sr8Tb4 cuboctahedra, edges with six equivalent Tb(1)Sr12 cuboctahedra, edges with twelve equivalent Sr(1)Sr8Tb4 cuboctahedra, faces with four equivalent Tb(1)Sr12 cuboctahedra, and faces with sixteen equivalent Sr(1)Sr8Tb4 cuboctahedra. There are a spread of Sr(1)-Sr(1) bond distances ranging from 3.94-4.19 Å. There are two shorter (3.98 Å) and two longer (4.07 Å) Sr(1)-Tb(1) bond lengths. Tb(1) is bonded to twelve equivalent Sr(1) atoms to form TbSr12 cuboctahedra that share corners with six equivalent Tb(1)Sr12 cuboctahedra, corners with twelve equivalent Sr(1)Sr8Tb4 cuboctahedra, edges with eighteen equivalent Sr(1)Sr8Tb4 cuboctahedra, faces with eight equivalent Tb(1)Sr12 cuboctahedra, and faces with twelve equivalent Sr(1)Sr8Tb4 cuboctahedra.