Ce2Ni21B6 crystallizes in the cubic Fm-3m space group. Ce(1) is bonded to four equivalent Ni(2) and twelve equivalent Ni(3) atoms to form distorted CeNi16 tetrahedra that share edges with six equivalent Ce(1)Ni16 tetrahedra and faces with four equivalent Ni(1)Ni12 cuboctahedra. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to twelve equivalent Ni(3) atoms to form NiNi12 cuboctahedra that share faces with eight equivalent Ce(1)Ni16 tetrahedra. In the second Ni site, Ni(2) is bonded to one Ce(1) and three equivalent B(1) atoms to form a mixture of distorted corner and edge-sharing NiCeB3 tetrahedra. In the third Ni site, Ni(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Ce(1), one Ni(1), and two equivalent B(1) atoms. B(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms.
Ce2Ni21B6 crystallizes in the cubic Fm-3m space group. Ce(1) is bonded to four equivalent Ni(2) and twelve equivalent Ni(3) atoms to form distorted CeNi16 tetrahedra that share edges with six equivalent Ce(1)Ni16 tetrahedra and faces with four equivalent Ni(1)Ni12 cuboctahedra. All Ce(1)-Ni(2) bond lengths are 2.53 Å. All Ce(1)-Ni(3) bond lengths are 2.94 Å. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to twelve equivalent Ni(3) atoms to form NiNi12 cuboctahedra that share faces with eight equivalent Ce(1)Ni16 tetrahedra. All Ni(1)-Ni(3) bond lengths are 2.55 Å. In the second Ni site, Ni(2) is bonded to one Ce(1) and three equivalent B(1) atoms to form a mixture of distorted corner and edge-sharing NiCeB3 tetrahedra. All Ni(2)-B(1) bond lengths are 2.13 Å. In the third Ni site, Ni(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Ce(1), one Ni(1), and two equivalent B(1) atoms. Both Ni(3)-B(1) bond lengths are 2.09 Å. B(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms.