 This causes the first ionization energies of the 7d transition metals to be smaller than those of their lighter congeners.Calculations predict that the 7d electrons of element 164 (unhexquadium) should participate very readily in chemical reactions, so that unhexquadium should be able to show stable +6 and +4 oxidation states in addition to the normal +2 state in aqueous solutions with strong ligands.Unhexquadium should thus be able to form compounds like Uhq(CO)4, Uhq(PF3)4 (both tetrahedral like the corresponding palladium compounds), and (linear), which is very different behavior from that of lead, which unhexquadium would be a heavier homologue of if not for relativistic effects.