UCeB8 crystallizes in the orthorhombic Cmmm space group. U(1) is bonded in a 18-coordinate geometry to two equivalent B(5), four equivalent B(1), four equivalent B(2), four equivalent B(3), and four equivalent B(4) atoms. Ce(1) is bonded in a 18-coordinate geometry to two equivalent B(4), four equivalent B(1), four equivalent B(2), four equivalent B(3), and four equivalent B(5) atoms. There are five inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent Ce(1), one B(1), two equivalent B(2), and two equivalent B(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent Ce(1), one B(5), two equivalent B(1), and two equivalent B(3) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent Ce(1), one B(4), two equivalent B(1), and two equivalent B(2) atoms. In the fourth B site, B(4) is bonded in a distorted trigonal planar geometry to four equivalent U(1), two equivalent Ce(1), one B(4), and two equivalent B(3) atoms. In the fifth B site, B(5) is bonded in a 3-coordinate geometry to two equivalent U(1), four equivalent Ce(1), one B(5), and two equivalent B(2) atoms.
UCeB8 crystallizes in the orthorhombic Cmmm space group. U(1) is bonded in a 18-coordinate geometry to two equivalent B(5), four equivalent B(1), four equivalent B(2), four equivalent B(3), and four equivalent B(4) atoms. Both U(1)-B(5) bond lengths are 3.02 Å. All U(1)-B(1) bond lengths are 2.70 Å. All U(1)-B(2) bond lengths are 2.77 Å. All U(1)-B(3) bond lengths are 2.72 Å. All U(1)-B(4) bond lengths are 2.90 Å. Ce(1) is bonded in a 18-coordinate geometry to two equivalent B(4), four equivalent B(1), four equivalent B(2), four equivalent B(3), and four equivalent B(5) atoms. Both Ce(1)-B(4) bond lengths are 3.01 Å. All Ce(1)-B(1) bond lengths are 2.72 Å. All Ce(1)-B(2) bond lengths are 2.77 Å. All Ce(1)-B(3) bond lengths are 2.81 Å. All Ce(1)-B(5) bond lengths are 2.89 Å. There are five inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent Ce(1), one B(1), two equivalent B(2), and two equivalent B(3) atoms. The B(1)-B(1) bond length is 1.61 Å. Both B(1)-B(2) bond lengths are 1.76 Å. Both B(1)-B(3) bond lengths are 1.77 Å. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent Ce(1), one B(5), two equivalent B(1), and two equivalent B(3) atoms. The B(2)-B(5) bond length is 1.70 Å. There is one shorter (1.80 Å) and one longer (1.85 Å) B(2)-B(3) bond length. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent Ce(1), one B(4), two equivalent B(1), and two equivalent B(2) atoms. The B(3)-B(4) bond length is 1.71 Å. In the fourth B site, B(4) is bonded in a distorted trigonal planar geometry to four equivalent U(1), two equivalent Ce(1), one B(4), and two equivalent B(3) atoms. The B(4)-B(4) bond length is 1.75 Å. In the fifth B site, B(5) is bonded in a 3-coordinate geometry to two equivalent U(1), four equivalent Ce(1), one B(5), and two equivalent B(2) atoms. The B(5)-B(5) bond length is 1.78 Å.