Tb3Pm is Magnesium-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to eight Tb(1,1) and four equivalent Pm(1) atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent Pm(1)Tb12 cuboctahedra; corners with fourteen Tb(1,1)Tb8Pm4 cuboctahedra; edges with six equivalent Pm(1)Tb12 cuboctahedra; edges with twelve Tb(1,1)Tb8Pm4 cuboctahedra; faces with four equivalent Pm(1)Tb12 cuboctahedra; and faces with sixteen Tb(1,1,1)Tb8Pm4 cuboctahedra. In the second Tb site, Tb(1) is bonded to eight Tb(1,1,1) and four equivalent Pm(1) atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent Pm(1)Tb12 cuboctahedra; corners with fourteen Tb(1,1)Tb8Pm4 cuboctahedra; edges with six equivalent Pm(1)Tb12 cuboctahedra; edges with twelve Tb(1,1,1)Tb8Pm4 cuboctahedra; faces with four equivalent Pm(1)Tb12 cuboctahedra; and faces with sixteen Tb(1,1,1)Tb8Pm4 cuboctahedra. In the third Tb site, Tb(1) is bonded to eight Tb(1,1) and four equivalent Pm(1) atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent Pm(1)Tb12 cuboctahedra; corners with fourteen Tb(1,1)Tb8Pm4 cuboctahedra; edges with six equivalent Pm(1)Tb12 cuboctahedra; edges with twelve Tb(1,1)Tb8Pm4 cuboctahedra; faces with four equivalent Pm(1)Tb12 cuboctahedra; and faces with sixteen Tb(1,1,1)Tb8Pm4 cuboctahedra. Pm(1) is bonded to twelve Tb(1,1,1) atoms to form PmTb12 cuboctahedra that share corners with six equivalent Pm(1)Tb12 cuboctahedra; corners with twelve Tb(1,1)Tb8Pm4 cuboctahedra; edges with eighteen Tb(1,1,1)Tb8Pm4 cuboctahedra; faces with eight equivalent Pm(1)Tb12 cuboctahedra; and faces with twelve Tb(1,1,1)Tb8Pm4 cuboctahedra.
Tb3Pm is Magnesium-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to eight Tb(1,1) and four equivalent Pm(1) atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent Pm(1)Tb12 cuboctahedra; corners with fourteen Tb(1,1)Tb8Pm4 cuboctahedra; edges with six equivalent Pm(1)Tb12 cuboctahedra; edges with twelve Tb(1,1)Tb8Pm4 cuboctahedra; faces with four equivalent Pm(1)Tb12 cuboctahedra; and faces with sixteen Tb(1,1,1)Tb8Pm4 cuboctahedra. There are a spread of Tb(1)-Tb(1,1) bond distances ranging from 3.59-3.69 Å. There are two shorter (3.62 Å) and two longer (3.65 Å) Tb(1)-Pm(1) bond lengths. In the second Tb site, Tb(1) is bonded to eight Tb(1,1,1) and four equivalent Pm(1) atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent Pm(1)Tb12 cuboctahedra; corners with fourteen Tb(1,1)Tb8Pm4 cuboctahedra; edges with six equivalent Pm(1)Tb12 cuboctahedra; edges with twelve Tb(1,1,1)Tb8Pm4 cuboctahedra; faces with four equivalent Pm(1)Tb12 cuboctahedra; and faces with sixteen Tb(1,1,1)Tb8Pm4 cuboctahedra. There are a spread of Tb(1)-Tb(1,1) bond distances ranging from 3.59-3.69 Å. There are two shorter (3.62 Å) and two longer (3.65 Å) Tb(1)-Pm(1) bond lengths. In the third Tb site, Tb(1) is bonded to eight Tb(1,1) and four equivalent Pm(1) atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent Pm(1)Tb12 cuboctahedra; corners with fourteen Tb(1,1)Tb8Pm4 cuboctahedra; edges with six equivalent Pm(1)Tb12 cuboctahedra; edges with twelve Tb(1,1)Tb8Pm4 cuboctahedra; faces with four equivalent Pm(1)Tb12 cuboctahedra; and faces with sixteen Tb(1,1,1)Tb8Pm4 cuboctahedra. There are two shorter (3.62 Å) and two longer (3.65 Å) Tb(1)-Pm(1) bond lengths. Pm(1) is bonded to twelve Tb(1,1,1) atoms to form PmTb12 cuboctahedra that share corners with six equivalent Pm(1)Tb12 cuboctahedra; corners with twelve Tb(1,1)Tb8Pm4 cuboctahedra; edges with eighteen Tb(1,1,1)Tb8Pm4 cuboctahedra; faces with eight equivalent Pm(1)Tb12 cuboctahedra; and faces with twelve Tb(1,1,1)Tb8Pm4 cuboctahedra.