ThTm3 is Magnesium-derived structured and crystallizes in the hexagonal P6_3/mmc space group. Th(1) is bonded to twelve equivalent Tm(1) atoms to form ThTm12 cuboctahedra that share corners with six equivalent Th(1)Tm12 cuboctahedra, corners with twelve equivalent Tm(1)Tm8Th4 cuboctahedra, edges with eighteen equivalent Tm(1)Tm8Th4 cuboctahedra, faces with eight equivalent Th(1)Tm12 cuboctahedra, and faces with twelve equivalent Tm(1)Tm8Th4 cuboctahedra. Tm(1) is bonded to four equivalent Th(1) and eight equivalent Tm(1) atoms to form TmTm8Th4 cuboctahedra that share corners with four equivalent Th(1)Tm12 cuboctahedra, corners with fourteen equivalent Tm(1)Tm8Th4 cuboctahedra, edges with six equivalent Th(1)Tm12 cuboctahedra, edges with twelve equivalent Tm(1)Tm8Th4 cuboctahedra, faces with four equivalent Th(1)Tm12 cuboctahedra, and faces with sixteen equivalent Tm(1)Tm8Th4 cuboctahedra.
ThTm3 is Magnesium-derived structured and crystallizes in the hexagonal P6_3/mmc space group. Th(1) is bonded to twelve equivalent Tm(1) atoms to form ThTm12 cuboctahedra that share corners with six equivalent Th(1)Tm12 cuboctahedra, corners with twelve equivalent Tm(1)Tm8Th4 cuboctahedra, edges with eighteen equivalent Tm(1)Tm8Th4 cuboctahedra, faces with eight equivalent Th(1)Tm12 cuboctahedra, and faces with twelve equivalent Tm(1)Tm8Th4 cuboctahedra. There are six shorter (3.51 Å) and six longer (3.57 Å) Th(1)-Tm(1) bond lengths. Tm(1) is bonded to four equivalent Th(1) and eight equivalent Tm(1) atoms to form TmTm8Th4 cuboctahedra that share corners with four equivalent Th(1)Tm12 cuboctahedra, corners with fourteen equivalent Tm(1)Tm8Th4 cuboctahedra, edges with six equivalent Th(1)Tm12 cuboctahedra, edges with twelve equivalent Tm(1)Tm8Th4 cuboctahedra, faces with four equivalent Th(1)Tm12 cuboctahedra, and faces with sixteen equivalent Tm(1)Tm8Th4 cuboctahedra. There are a spread of Tm(1)-Tm(1) bond distances ranging from 3.50-3.57 Å.