Tb2PtAl3 crystallizes in the trigonal R-3m space group. Tb(1) is bonded in a 12-coordinate geometry to three equivalent Pt(1) and nine equivalent Al(1) atoms. Pt(1) is bonded to six equivalent Tb(1) and six equivalent Al(1) atoms to form PtTb6Al6 cuboctahedra that share corners with six equivalent Pt(1)Tb6Al6 cuboctahedra, corners with twelve equivalent Al(1)Tb6Al4Pt2 cuboctahedra, edges with six equivalent Pt(1)Tb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Tb6Al4Pt2 cuboctahedra. Al(1) is bonded to six equivalent Tb(1), two equivalent Pt(1), and four equivalent Al(1) atoms to form distorted AlTb6Al4Pt2 cuboctahedra that share corners with four equivalent Pt(1)Tb6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Tb6Al4Pt2 cuboctahedra, edges with six equivalent Al(1)Tb6Al4Pt2 cuboctahedra, faces with six equivalent Pt(1)Tb6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Tb6Al4Pt2 cuboctahedra.
Tb2PtAl3 crystallizes in the trigonal R-3m space group. Tb(1) is bonded in a 12-coordinate geometry to three equivalent Pt(1) and nine equivalent Al(1) atoms. All Tb(1)-Pt(1) bond lengths are 3.25 Å. There are three shorter (3.18 Å) and six longer (3.23 Å) Tb(1)-Al(1) bond lengths. Pt(1) is bonded to six equivalent Tb(1) and six equivalent Al(1) atoms to form PtTb6Al6 cuboctahedra that share corners with six equivalent Pt(1)Tb6Al6 cuboctahedra, corners with twelve equivalent Al(1)Tb6Al4Pt2 cuboctahedra, edges with six equivalent Pt(1)Tb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Tb6Al4Pt2 cuboctahedra. All Pt(1)-Al(1) bond lengths are 2.72 Å. Al(1) is bonded to six equivalent Tb(1), two equivalent Pt(1), and four equivalent Al(1) atoms to form distorted AlTb6Al4Pt2 cuboctahedra that share corners with four equivalent Pt(1)Tb6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Tb6Al4Pt2 cuboctahedra, edges with six equivalent Al(1)Tb6Al4Pt2 cuboctahedra, faces with six equivalent Pt(1)Tb6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Tb6Al4Pt2 cuboctahedra. All Al(1)-Al(1) bond lengths are 2.78 Å.