UCeZn17 crystallizes in the trigonal R3m space group. U(1) is bonded in a 19-coordinate geometry to one Zn(6), three equivalent Zn(3), three equivalent Zn(4), six equivalent Zn(1), and six equivalent Zn(2) atoms. Ce(1) is bonded in a 19-coordinate geometry to one Zn(5), three equivalent Zn(2), three equivalent Zn(4), six equivalent Zn(1), and six equivalent Zn(3) atoms. There are six inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 12-coordinate geometry to one U(1), one Ce(1), one Zn(5), one Zn(6), two equivalent Zn(1), two equivalent Zn(2), two equivalent Zn(3), and two equivalent Zn(4) atoms. In the second Zn site, Zn(2) is bonded in a 12-coordinate geometry to two equivalent U(1), one Ce(1), one Zn(6), two equivalent Zn(3), two equivalent Zn(4), and four equivalent Zn(1) atoms. In the third Zn site, Zn(3) is bonded to one U(1), two equivalent Ce(1), one Zn(5), two equivalent Zn(2), two equivalent Zn(4), and four equivalent Zn(1) atoms to form distorted ZnCe2UZn9 cuboctahedra that share corners with two equivalent Zn(3)Ce2UZn9 cuboctahedra, corners with five equivalent Zn(4)CeUZn10 cuboctahedra, edges with three equivalent Zn(4)CeUZn10 cuboctahedra, edges with four equivalent Zn(3)Ce2UZn9 cuboctahedra, faces with three equivalent Zn(4)CeUZn10 cuboctahedra, and faces with four equivalent Zn(3)Ce2UZn9 cuboctahedra. In the fourth Zn site, Zn(4) is bonded to one U(1), one Ce(1), one Zn(5), one Zn(6), two equivalent Zn(2), two equivalent Zn(3), and four equivalent Zn(1) atoms to form distorted ZnCeUZn10 cuboctahedra that share corners with four equivalent Zn(4)CeUZn10 cuboctahedra, corners with five equivalent Zn(3)Ce2UZn9 cuboctahedra, edges with three equivalent Zn(3)Ce2UZn9 cuboctahedra, faces with three equivalent Zn(3)Ce2UZn9 cuboctahedra, and faces with four equivalent Zn(4)CeUZn10 cuboctahedra. In the fifth Zn site, Zn(5) is bonded in a 14-coordinate geometry to one Ce(1), one Zn(6), three equivalent Zn(3), three equivalent Zn(4), and six equivalent Zn(1) atoms. In the sixth Zn site, Zn(6) is bonded in a 14-coordinate geometry to one U(1), one Zn(5), three equivalent Zn(2), three equivalent Zn(4), and six equivalent Zn(1) atoms.
UCeZn17 crystallizes in the trigonal R3m space group. U(1) is bonded in a 19-coordinate geometry to one Zn(6), three equivalent Zn(3), three equivalent Zn(4), six equivalent Zn(1), and six equivalent Zn(2) atoms. The U(1)-Zn(6) bond length is 3.10 Å. All U(1)-Zn(3) bond lengths are 3.21 Å. All U(1)-Zn(4) bond lengths are 3.42 Å. All U(1)-Zn(1) bond lengths are 3.16 Å. There are three shorter (3.35 Å) and three longer (3.49 Å) U(1)-Zn(2) bond lengths. Ce(1) is bonded in a 19-coordinate geometry to one Zn(5), three equivalent Zn(2), three equivalent Zn(4), six equivalent Zn(1), and six equivalent Zn(3) atoms. The Ce(1)-Zn(5) bond length is 3.13 Å. All Ce(1)-Zn(2) bond lengths are 3.23 Å. All Ce(1)-Zn(4) bond lengths are 3.44 Å. All Ce(1)-Zn(1) bond lengths are 3.18 Å. There are three shorter (3.36 Å) and three longer (3.47 Å) Ce(1)-Zn(3) bond lengths. There are six inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a 12-coordinate geometry to one U(1), one Ce(1), one Zn(5), one Zn(6), two equivalent Zn(1), two equivalent Zn(2), two equivalent Zn(3), and two equivalent Zn(4) atoms. The Zn(1)-Zn(5) bond length is 2.99 Å. The Zn(1)-Zn(6) bond length is 3.00 Å. There is one shorter (2.66 Å) and one longer (2.68 Å) Zn(1)-Zn(1) bond length. There is one shorter (2.73 Å) and one longer (2.77 Å) Zn(1)-Zn(2) bond length. There is one shorter (2.72 Å) and one longer (2.79 Å) Zn(1)-Zn(3) bond length. There is one shorter (2.60 Å) and one longer (2.61 Å) Zn(1)-Zn(4) bond length. In the second Zn site, Zn(2) is bonded in a 12-coordinate geometry to two equivalent U(1), one Ce(1), one Zn(6), two equivalent Zn(3), two equivalent Zn(4), and four equivalent Zn(1) atoms. The Zn(2)-Zn(6) bond length is 2.85 Å. Both Zn(2)-Zn(3) bond lengths are 2.56 Å. Both Zn(2)-Zn(4) bond lengths are 2.62 Å. In the third Zn site, Zn(3) is bonded to one U(1), two equivalent Ce(1), one Zn(5), two equivalent Zn(2), two equivalent Zn(4), and four equivalent Zn(1) atoms to form distorted ZnCe2UZn9 cuboctahedra that share corners with two equivalent Zn(3)Ce2UZn9 cuboctahedra, corners with five equivalent Zn(4)CeUZn10 cuboctahedra, edges with three equivalent Zn(4)CeUZn10 cuboctahedra, edges with four equivalent Zn(3)Ce2UZn9 cuboctahedra, faces with three equivalent Zn(4)CeUZn10 cuboctahedra, and faces with four equivalent Zn(3)Ce2UZn9 cuboctahedra. The Zn(3)-Zn(5) bond length is 2.88 Å. Both Zn(3)-Zn(4) bond lengths are 2.64 Å. In the fourth Zn site, Zn(4) is bonded to one U(1), one Ce(1), one Zn(5), one Zn(6), two equivalent Zn(2), two equivalent Zn(3), and four equivalent Zn(1) atoms to form distorted ZnCeUZn10 cuboctahedra that share corners with four equivalent Zn(4)CeUZn10 cuboctahedra, corners with five equivalent Zn(3)Ce2UZn9 cuboctahedra, edges with three equivalent Zn(3)Ce2UZn9 cuboctahedra, faces with three equivalent Zn(3)Ce2UZn9 cuboctahedra, and faces with four equivalent Zn(4)CeUZn10 cuboctahedra. The Zn(4)-Zn(5) bond length is 2.75 Å. The Zn(4)-Zn(6) bond length is 2.72 Å. In the fifth Zn site, Zn(5) is bonded in a 14-coordinate geometry to one Ce(1), one Zn(6), three equivalent Zn(3), three equivalent Zn(4), and six equivalent Zn(1) atoms. The Zn(5)-Zn(6) bond length is 2.70 Å. In the sixth Zn site, Zn(6) is bonded in a 14-coordinate geometry to one U(1), one Zn(5), three equivalent Zn(2), three equivalent Zn(4), and six equivalent Zn(1) atoms.