Ionization potentials of the superheavy element livermorium (Z = 116)

Ionization potentials (IPs) of the superheavy element (SHE) livermorium (Lv) and its ions Lvⁿ⁺ (n = 1, …, 6) are obtained using the multiconfiguration Dirac-Hartree-Fock method. The effects of electron correlation in the subshells {6s, 6p, 6d, 7s, 7p} are taken into account, together with the Breit interaction and quantum electrodynamic (QED) effects. In Lv, the strong relativistic effect causes a large splitting between the energies of the 7p_1/2 and 7p_3/2 orbitals, which results in a large difference between IP₃ and IP₂. As a consequence, the behavior of the IPs of Lv differs from that of the lighter oxygen group elements: among the IP_n ^Z (Z = Se, Te, Po, Lv; n = 1, …, 6), IP_1,2 ^Lv are the smallest, whereas IP_3,4,5,6 ^Lv are the second largest among the IP_3,4,5,6 ^Z. This jump in IP can be taken to be a natural characteristic of SHEs because the calculations of the difference between IP₃ and IP₂ are only weakly affected by electron correlation, the Breit interaction, and QED effects, with only the relativistic effect being significant. We also show that the energies and IPs of neutral Lv and Lv⁺ are clearly influenced by the electron correlation effect in the subshells {6s, 6p, 6d}. The Breit interaction and QED have an effect on the energies that has an exponential dependence on the atomic number, although they have only a weak influence on the IPs. The analysis of the stabilities of the 2+, 4+, and 6 + states of Lv shows good agreement with predictions from other studies.