The sole Ni-based cluster in the CSD is the complex [Ni II 2Th IV 5O4(OH)2(H1TBC [8])2(dmf)5(MeOH)2] (28; Fig. ). The metallic skeleton of 28 describes a highly distorted {Ni2Th4} octahedron, capped on one face by a fifth Th IV ion, and stabilised by the presence of four O 2-ions which sit on the four equatorial edges of the {Ni2Th2} square. Three are µ4-bridging (2 x {Th3Ni}, 1 x {Th2Ni2}), and one is µ3-bridging (1 x {Th3}). The two Th IV apices are connected to this square by eight {OR} alkoxides, one on each edge. Six are derived from µ-O(Ph) atoms of the calix [8]arene ligands, with the remaining two, on neighbouring edges, being µ3-OH ions. The latter further bridge to the remaining Th IV ion, which caps a {Ni2Th} face of the octahedron. The hepta-deprotonated H1TBC [8]