Iridium ground state electronic configuration

The electronic ground-state configuration of the free neutral atom of element 109 has been predicted to be 5f 6d 7s and thus it should belong to the group VIII elements of the periodic table [75]. Element 109 is expected to have a chemical behavior similar to iridium but may exhibit an even more noble character [75]. The oxidation states 6+ [77], 3 -H [99], and 1 -t- [78] have been predicted to be stable, and a wide variety of valence states are anticipated in aqueous solution for element 109 [75], Like Ir, element 109 should form numerous solution complexes [75], Some of the predicted chemical properties of element 109 are given in Table 13.10. 

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