Ionization potentials, electron affinities and stabilities of oxidation states

The destabilization of the 6d orbitals is a reason for an increas in the stability of the highest oxidation states also at the end of the 6d series, like of the 

3+ and 5+ states of element 111 (the 1+ oxidation state of element 111 was predicted to be unstable), or of the 4+ state of element 112. Due to a relatively high electron affinity of element 111, the 1- oxidation state may be accessible with appropriate ligands. The 0 oxidation state will dominate for element 112 (the EA is 0). 

For element 115, the 1+ oxidation state should be important, since an electron is added to the spin-orbit destabilized 7p3/2 orbital. Consequently, element 116 should be stable in the 2+ oxidation state. Element 117 has one electron missing in the 7p3/2 shell. Due to the relativistic stabilization of the 7pi/2 shell it should, therefore, be more stable in the 1+ and 3+ oxidation states compared to the lighter homologues, but less stable in the 5+ and 7+ oxidation states. The 1-oxidation state becomes less important in group 17 due to the destabilization of the 7p3/2 orbital (the EA of element 117 is the smallest in the group [20]). For element 118, oxidation states 2+ and 4+ will be more important than the 6+ state because of the relativistically stabilized l n electrons. It was predicted to form compounds with F and even Cl. 

Stabilities of various oxidation states of heavier elements are discussed in Ref. 20. Different oxidation sates than those of the lighter homologs are possible due to different ionization processes and complex electronic configurations. 

Ionic radii can be defined either by the maximum of the radial charge density, r, or the expectation value, (r , of an outer valence orbital. The DF 

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