Gd2Zn17 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 18-coordinate geometry to two equivalent Zn(4), two equivalent Zn(5), two equivalent Zn(6), four equivalent Zn(8), and eight equivalent Zn(7) atoms. In the second Gd site, Gd(2) is bonded in a 20-coordinate geometry to two equivalent Zn(1), two equivalent Zn(3), two equivalent Zn(4), two equivalent Zn(5), two equivalent Zn(6), two equivalent Zn(8), four equivalent Zn(2), and four equivalent Zn(7) atoms. There are eight inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 14-coordinate geometry to one Gd(2), one Zn(1), one Zn(3), one Zn(8), two equivalent Zn(2), two equivalent Zn(4), two equivalent Zn(5), two equivalent Zn(6), and two equivalent Zn(7) atoms. In the second Zn site, Zn(2) is bonded to two equivalent Gd(2), two equivalent Zn(1), two equivalent Zn(4), two equivalent Zn(6), two equivalent Zn(7), and two equivalent Zn(8) atoms to form ZnGd2Zn10 cuboctahedra that share corners with two equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with two equivalent Zn(3)Gd2Zn10 cuboctahedra, corners with two equivalent Zn(8)Gd3Zn9 cuboctahedra, corners with eight equivalent Zn(7)Gd3Zn9 cuboctahedra, edges with two equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with four equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(3)Gd2Zn10 cuboctahedra, faces with two equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(8)Gd3Zn9 cuboctahedra, and faces with four equivalent Zn(2)Gd2Zn10 cuboctahedra. In the third Zn site, Zn(3) is bonded to two equivalent Gd(2), two equivalent Zn(1), four equivalent Zn(5), and four equivalent Zn(7) atoms to form ZnGd2Zn10 cuboctahedra that share corners with four equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with four equivalent Zn(7)Gd3Zn9 cuboctahedra, corners with six equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with two equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with four equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(3)Gd2Zn10 cuboctahedra, faces with four equivalent Zn(2)Gd2Zn10 cuboctahedra, and faces with four equivalent Zn(7)Gd3Zn9 cuboctahedra. In the fourth Zn site, Zn(4) is bonded in a 12-coordinate geometry to one Gd(1), one Gd(2), one Zn(4), one Zn(6), two equivalent Zn(1), two equivalent Zn(2), two equivalent Zn(7), and two equivalent Zn(8) atoms. In the fifth Zn site, Zn(5) is bonded in a 12-coordinate geometry to one Gd(1), one Gd(2), one Zn(5), one Zn(6), two equivalent Zn(1), two equivalent Zn(3), and four equivalent Zn(7) atoms. In the sixth Zn site, Zn(6) is bonded in a 12-coordinate geometry to one Gd(1), one Gd(2), one Zn(4), one Zn(5), two equivalent Zn(1), two equivalent Zn(2), two equivalent Zn(7), and two equivalent Zn(8) atoms. In the seventh Zn site, Zn(7) is bonded to one Gd(2), two equivalent Gd(1), one Zn(1), one Zn(2), one Zn(3), one Zn(4), one Zn(6), one Zn(7), one Zn(8), and two equivalent Zn(5) atoms to form distorted ZnGd3Zn9 cuboctahedra that share  a cornercorner with one Zn(3)Gd2Zn10 cuboctahedra, corners with three equivalent Zn(8)Gd3Zn9 cuboctahedra, corners with four equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with seven equivalent Zn(7)Gd3Zn9 cuboctahedra,  an edgeedge with one Zn(3)Gd2Zn10 cuboctahedra, edges with two equivalent Zn(2)Gd2Zn10 cuboctahedra, edges with two equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with three equivalent Zn(7)Gd3Zn9 cuboctahedra,  a faceface with one Zn(2)Gd2Zn10 cuboctahedra,  a faceface with one Zn(3)Gd2Zn10 cuboctahedra, faces with three equivalent Zn(8)Gd3Zn9 cuboctahedra, and faces with five equivalent Zn(7)Gd3Zn9 cuboctahedra. In the eighth Zn site, Zn(8) is bonded to one Gd(2), two equivalent Gd(1), one Zn(1), two equivalent Zn(2), two equivalent Zn(4), two equivalent Zn(6), and two equivalent Zn(7) atoms to form distorted ZnGd3Zn9 cuboctahedra that share corners with two equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with three equivalent Zn(3)Gd2Zn10 cuboctahedra, corners with four equivalent Zn(8)Gd3Zn9 cuboctahedra, corners with six equivalent Zn(7)Gd3Zn9 cuboctahedra,  an edgeedge with one Zn(3)Gd2Zn10 cuboctahedra,  an edgeedge with one Zn(8)Gd3Zn9 cuboctahedra, edges with two equivalent Zn(2)Gd2Zn10 cuboctahedra, edges with four equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(2)Gd2Zn10 cuboctahedra, faces with two equivalent Zn(8)Gd3Zn9 cuboctahedra, and faces with six equivalent Zn(7)Gd3Zn9 cuboctahedra.
Gd2Zn17 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 18-coordinate geometry to two equivalent Zn(4), two equivalent Zn(5), two equivalent Zn(6), four equivalent Zn(8), and eight equivalent Zn(7) atoms. Both Gd(1)-Zn(4) bond lengths are 3.16 Å. Both Gd(1)-Zn(5) bond lengths are 3.17 Å. Both Gd(1)-Zn(6) bond lengths are 3.16 Å. There are two shorter (3.25 Å) and two longer (3.45 Å) Gd(1)-Zn(8) bond lengths. There are four shorter (3.25 Å) and four longer (3.45 Å) Gd(1)-Zn(7) bond lengths. In the second Gd site, Gd(2) is bonded in a 20-coordinate geometry to two equivalent Zn(1), two equivalent Zn(3), two equivalent Zn(4), two equivalent Zn(5), two equivalent Zn(6), two equivalent Zn(8), four equivalent Zn(2), and four equivalent Zn(7) atoms. Both Gd(2)-Zn(1) bond lengths are 3.03 Å. Both Gd(2)-Zn(3) bond lengths are 3.41 Å. Both Gd(2)-Zn(4) bond lengths are 3.21 Å. Both Gd(2)-Zn(5) bond lengths are 3.21 Å. Both Gd(2)-Zn(6) bond lengths are 3.21 Å. Both Gd(2)-Zn(8) bond lengths are 3.37 Å. All Gd(2)-Zn(2) bond lengths are 3.41 Å. All Gd(2)-Zn(7) bond lengths are 3.37 Å. There are eight inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 14-coordinate geometry to one Gd(2), one Zn(1), one Zn(3), one Zn(8), two equivalent Zn(2), two equivalent Zn(4), two equivalent Zn(5), two equivalent Zn(6), and two equivalent Zn(7) atoms. The Zn(1)-Zn(1) bond length is 2.64 Å. The Zn(1)-Zn(3) bond length is 2.76 Å. The Zn(1)-Zn(8) bond length is 2.88 Å. Both Zn(1)-Zn(2) bond lengths are 2.76 Å. Both Zn(1)-Zn(4) bond lengths are 3.03 Å. Both Zn(1)-Zn(5) bond lengths are 3.03 Å. Both Zn(1)-Zn(6) bond lengths are 3.03 Å. Both Zn(1)-Zn(7) bond lengths are 2.88 Å. In the second Zn site, Zn(2) is bonded to two equivalent Gd(2), two equivalent Zn(1), two equivalent Zn(4), two equivalent Zn(6), two equivalent Zn(7), and two equivalent Zn(8) atoms to form ZnGd2Zn10 cuboctahedra that share corners with two equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with two equivalent Zn(3)Gd2Zn10 cuboctahedra, corners with two equivalent Zn(8)Gd3Zn9 cuboctahedra, corners with eight equivalent Zn(7)Gd3Zn9 cuboctahedra, edges with two equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with four equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(3)Gd2Zn10 cuboctahedra, faces with two equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(8)Gd3Zn9 cuboctahedra, and faces with four equivalent Zn(2)Gd2Zn10 cuboctahedra. Both Zn(2)-Zn(4) bond lengths are 2.60 Å. Both Zn(2)-Zn(6) bond lengths are 2.60 Å. Both Zn(2)-Zn(7) bond lengths are 2.66 Å. Both Zn(2)-Zn(8) bond lengths are 2.66 Å. In the third Zn site, Zn(3) is bonded to two equivalent Gd(2), two equivalent Zn(1), four equivalent Zn(5), and four equivalent Zn(7) atoms to form ZnGd2Zn10 cuboctahedra that share corners with four equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with four equivalent Zn(7)Gd3Zn9 cuboctahedra, corners with six equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with two equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with four equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(3)Gd2Zn10 cuboctahedra, faces with four equivalent Zn(2)Gd2Zn10 cuboctahedra, and faces with four equivalent Zn(7)Gd3Zn9 cuboctahedra. All Zn(3)-Zn(5) bond lengths are 2.59 Å. All Zn(3)-Zn(7) bond lengths are 2.66 Å. In the fourth Zn site, Zn(4) is bonded in a 12-coordinate geometry to one Gd(1), one Gd(2), one Zn(4), one Zn(6), two equivalent Zn(1), two equivalent Zn(2), two equivalent Zn(7), and two equivalent Zn(8) atoms. The Zn(4)-Zn(4) bond length is 2.67 Å. The Zn(4)-Zn(6) bond length is 2.78 Å. Both Zn(4)-Zn(7) bond lengths are 2.72 Å. Both Zn(4)-Zn(8) bond lengths are 2.70 Å. In the fifth Zn site, Zn(5) is bonded in a 12-coordinate geometry to one Gd(1), one Gd(2), one Zn(5), one Zn(6), two equivalent Zn(1), two equivalent Zn(3), and four equivalent Zn(7) atoms. The Zn(5)-Zn(5) bond length is 2.77 Å. The Zn(5)-Zn(6) bond length is 2.68 Å. There are two shorter (2.70 Å) and two longer (2.72 Å) Zn(5)-Zn(7) bond lengths. In the sixth Zn site, Zn(6) is bonded in a 12-coordinate geometry to one Gd(1), one Gd(2), one Zn(4), one Zn(5), two equivalent Zn(1), two equivalent Zn(2), two equivalent Zn(7), and two equivalent Zn(8) atoms. Both Zn(6)-Zn(7) bond lengths are 2.70 Å. Both Zn(6)-Zn(8) bond lengths are 2.72 Å. In the seventh Zn site, Zn(7) is bonded to one Gd(2), two equivalent Gd(1), one Zn(1), one Zn(2), one Zn(3), one Zn(4), one Zn(6), one Zn(7), one Zn(8), and two equivalent Zn(5) atoms to form distorted ZnGd3Zn9 cuboctahedra that share  a cornercorner with one Zn(3)Gd2Zn10 cuboctahedra, corners with three equivalent Zn(8)Gd3Zn9 cuboctahedra, corners with four equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with seven equivalent Zn(7)Gd3Zn9 cuboctahedra,  an edgeedge with one Zn(3)Gd2Zn10 cuboctahedra, edges with two equivalent Zn(2)Gd2Zn10 cuboctahedra, edges with two equivalent Zn(8)Gd3Zn9 cuboctahedra, edges with three equivalent Zn(7)Gd3Zn9 cuboctahedra,  a faceface with one Zn(2)Gd2Zn10 cuboctahedra,  a faceface with one Zn(3)Gd2Zn10 cuboctahedra, faces with three equivalent Zn(8)Gd3Zn9 cuboctahedra, and faces with five equivalent Zn(7)Gd3Zn9 cuboctahedra. The Zn(7)-Zn(7) bond length is 2.57 Å. The Zn(7)-Zn(8) bond length is 2.57 Å. In the eighth Zn site, Zn(8) is bonded to one Gd(2), two equivalent Gd(1), one Zn(1), two equivalent Zn(2), two equivalent Zn(4), two equivalent Zn(6), and two equivalent Zn(7) atoms to form distorted ZnGd3Zn9 cuboctahedra that share corners with two equivalent Zn(2)Gd2Zn10 cuboctahedra, corners with three equivalent Zn(3)Gd2Zn10 cuboctahedra, corners with four equivalent Zn(8)Gd3Zn9 cuboctahedra, corners with six equivalent Zn(7)Gd3Zn9 cuboctahedra,  an edgeedge with one Zn(3)Gd2Zn10 cuboctahedra,  an edgeedge with one Zn(8)Gd3Zn9 cuboctahedra, edges with two equivalent Zn(2)Gd2Zn10 cuboctahedra, edges with four equivalent Zn(7)Gd3Zn9 cuboctahedra, faces with two equivalent Zn(2)Gd2Zn10 cuboctahedra, faces with two equivalent Zn(8)Gd3Zn9 cuboctahedra, and faces with six equivalent Zn(7)Gd3Zn9 cuboctahedra.