Materials Data on Ac3Th by Materials Project
ThAc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Th is bonded to twelve equivalent Ac atoms to form ThAc12 cuboctahedra that share corners with six equivalent ThAc12 cuboctahedra, corners with twelve equivalent AcAc8Th4 cuboctahedra, edges with eighteen equivalent AcAc8Th4 cuboctahedra, faces with eight equivalent ThAc12 cuboctahedra, and faces with twelve equivalent AcAc8Th4 cuboctahedra. There are six shorter (3.85 Å) and six longer (3.89 Å) Th–Ac bond lengths. Ac is bonded to four equivalent Th and eight equivalent Ac atoms to form AcAc8Th4 cuboctahedra that share corners with four equivalent ThAc12 cuboctahedra, corners with fourteen equivalent AcAc8Th4 cuboctahedra, edges with six equivalent ThAc12 cuboctahedra, edges with twelve equivalent AcAc8Th4 cuboctahedra, faces with four equivalent ThAc12 cuboctahedra, and faces with sixteen equivalent AcAc8Th4 cuboctahedra. There are a spread of Ac–Ac bond distances ranging from 3.80–3.98 Å.