Tb2Zn17 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 20-coordinate geometry to two equivalent Zn(2), six equivalent Zn(1), six equivalent Zn(3), and six equivalent Zn(4) atoms. In the second Tb site, Tb(2) is bonded in a 18-coordinate geometry to six equivalent Zn(4) and twelve equivalent Zn(1) atoms. There are four inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one Tb(1), two equivalent Tb(2), one Zn(2), two equivalent Zn(1), two equivalent Zn(3), and four equivalent Zn(4) atoms to form distorted ZnTb3Zn9 cuboctahedra that share corners with five equivalent Zn(3)Tb2Zn10 cuboctahedra, corners with eight equivalent Zn(4)Tb2Zn10 cuboctahedra, corners with ten equivalent Zn(1)Tb3Zn9 cuboctahedra, edges with two equivalent Zn(4)Tb2Zn10 cuboctahedra, edges with three equivalent Zn(3)Tb2Zn10 cuboctahedra, edges with five equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with two equivalent Zn(3)Tb2Zn10 cuboctahedra, faces with eight equivalent Zn(1)Tb3Zn9 cuboctahedra, and faces with ten equivalent Zn(4)Tb2Zn10 cuboctahedra. In the second Zn site, Zn(2) is bonded in a 14-coordinate geometry to one Tb(1), one Zn(2), three equivalent Zn(1), three equivalent Zn(3), and six equivalent Zn(4) atoms. In the third Zn site, Zn(3) is bonded to two equivalent Tb(1), two equivalent Zn(2), four equivalent Zn(1), and four equivalent Zn(4) atoms to form ZnTb2Zn10 cuboctahedra that share corners with four equivalent Zn(3)Tb2Zn10 cuboctahedra, corners with eight equivalent Zn(4)Tb2Zn10 cuboctahedra, corners with ten equivalent Zn(1)Tb3Zn9 cuboctahedra, edges with four equivalent Zn(4)Tb2Zn10 cuboctahedra, edges with six equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with four equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with six equivalent Zn(3)Tb2Zn10 cuboctahedra, and faces with eight equivalent Zn(4)Tb2Zn10 cuboctahedra. In the fourth Zn site, Zn(4) is bonded to one Tb(1), one Tb(2), two equivalent Zn(2), two equivalent Zn(3), two equivalent Zn(4), and four equivalent Zn(1) atoms to form distorted ZnTb2Zn10 cuboctahedra that share corners with four equivalent Zn(3)Tb2Zn10 cuboctahedra, corners with eight equivalent Zn(1)Tb3Zn9 cuboctahedra, corners with twelve equivalent Zn(4)Tb2Zn10 cuboctahedra,  an edgeedge with one Zn(4)Tb2Zn10 cuboctahedra, edges with two equivalent Zn(3)Tb2Zn10 cuboctahedra, edges with two equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with four equivalent Zn(3)Tb2Zn10 cuboctahedra, faces with seven equivalent Zn(4)Tb2Zn10 cuboctahedra, and faces with ten equivalent Zn(1)Tb3Zn9 cuboctahedra.
Tb2Zn17 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 20-coordinate geometry to two equivalent Zn(2), six equivalent Zn(1), six equivalent Zn(3), and six equivalent Zn(4) atoms. Both Tb(1)-Zn(2) bond lengths are 3.05 Å. All Tb(1)-Zn(1) bond lengths are 3.30 Å. All Tb(1)-Zn(3) bond lengths are 3.35 Å. All Tb(1)-Zn(4) bond lengths are 3.16 Å. In the second Tb site, Tb(2) is bonded in a 18-coordinate geometry to six equivalent Zn(4) and twelve equivalent Zn(1) atoms. All Tb(2)-Zn(4) bond lengths are 3.11 Å. There are six shorter (3.18 Å) and six longer (3.42 Å) Tb(2)-Zn(1) bond lengths. There are four inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one Tb(1), two equivalent Tb(2), one Zn(2), two equivalent Zn(1), two equivalent Zn(3), and four equivalent Zn(4) atoms to form distorted ZnTb3Zn9 cuboctahedra that share corners with five equivalent Zn(3)Tb2Zn10 cuboctahedra, corners with eight equivalent Zn(4)Tb2Zn10 cuboctahedra, corners with ten equivalent Zn(1)Tb3Zn9 cuboctahedra, edges with two equivalent Zn(4)Tb2Zn10 cuboctahedra, edges with three equivalent Zn(3)Tb2Zn10 cuboctahedra, edges with five equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with two equivalent Zn(3)Tb2Zn10 cuboctahedra, faces with eight equivalent Zn(1)Tb3Zn9 cuboctahedra, and faces with ten equivalent Zn(4)Tb2Zn10 cuboctahedra. The Zn(1)-Zn(2) bond length is 2.84 Å. Both Zn(1)-Zn(1) bond lengths are 2.51 Å. Both Zn(1)-Zn(3) bond lengths are 2.60 Å. All Zn(1)-Zn(4) bond lengths are 2.69 Å. In the second Zn site, Zn(2) is bonded in a 14-coordinate geometry to one Tb(1), one Zn(2), three equivalent Zn(1), three equivalent Zn(3), and six equivalent Zn(4) atoms. The Zn(2)-Zn(2) bond length is 2.56 Å. All Zn(2)-Zn(3) bond lengths are 2.71 Å. All Zn(2)-Zn(4) bond lengths are 2.91 Å. In the third Zn site, Zn(3) is bonded to two equivalent Tb(1), two equivalent Zn(2), four equivalent Zn(1), and four equivalent Zn(4) atoms to form ZnTb2Zn10 cuboctahedra that share corners with four equivalent Zn(3)Tb2Zn10 cuboctahedra, corners with eight equivalent Zn(4)Tb2Zn10 cuboctahedra, corners with ten equivalent Zn(1)Tb3Zn9 cuboctahedra, edges with four equivalent Zn(4)Tb2Zn10 cuboctahedra, edges with six equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with four equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with six equivalent Zn(3)Tb2Zn10 cuboctahedra, and faces with eight equivalent Zn(4)Tb2Zn10 cuboctahedra. All Zn(3)-Zn(4) bond lengths are 2.56 Å. In the fourth Zn site, Zn(4) is bonded to one Tb(1), one Tb(2), two equivalent Zn(2), two equivalent Zn(3), two equivalent Zn(4), and four equivalent Zn(1) atoms to form distorted ZnTb2Zn10 cuboctahedra that share corners with four equivalent Zn(3)Tb2Zn10 cuboctahedra, corners with eight equivalent Zn(1)Tb3Zn9 cuboctahedra, corners with twelve equivalent Zn(4)Tb2Zn10 cuboctahedra,  an edgeedge with one Zn(4)Tb2Zn10 cuboctahedra, edges with two equivalent Zn(3)Tb2Zn10 cuboctahedra, edges with two equivalent Zn(1)Tb3Zn9 cuboctahedra, faces with four equivalent Zn(3)Tb2Zn10 cuboctahedra, faces with seven equivalent Zn(4)Tb2Zn10 cuboctahedra, and faces with ten equivalent Zn(1)Tb3Zn9 cuboctahedra. There is one shorter (2.56 Å) and one longer (2.67 Å) Zn(4)-Zn(4) bond length.