Materials Data on Ac3Sm by Materials Project
Ac3Sm is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ac is bonded to eight equivalent Ac and four equivalent Sm atoms to form AcAc8Sm4 cuboctahedra that share corners with four equivalent SmAc12 cuboctahedra, corners with fourteen equivalent AcAc8Sm4 cuboctahedra, edges with six equivalent SmAc12 cuboctahedra, edges with twelve equivalent AcAc8Sm4 cuboctahedra, faces with four equivalent SmAc12 cuboctahedra, and faces with sixteen equivalent AcAc8Sm4 cuboctahedra. There are a spread of Ac–Ac bond distances ranging from 3.89–3.98 Å. There are two shorter (3.88 Å) and two longer (3.93 Å) Ac–Sm bond lengths. Sm is bonded to twelve equivalent Ac atoms to form SmAc12 cuboctahedra that share corners with six equivalent SmAc12 cuboctahedra, corners with twelve equivalent AcAc8Sm4 cuboctahedra, edges with eighteen equivalent AcAc8Sm4 cuboctahedra, faces with eight equivalent SmAc12 cuboctahedra, and faces with twelve equivalent AcAc8Sm4 cuboctahedra.