QED corrections to the binding energy of the eka-radon(Z=118)negative ion

Are MCDF calculations 101% correct in the super-heavy elements range?

“…A survey of the literature shows that there are no direct QED calculations in the range of superheavy elements, except for the 1s shell. Many QED contributions have never been calculated for neutral superheavy elements, except for a very limited number of cases, notably in [60,78,41]. A systematic evaluation of all necessary contributions to order α 2 would represent a daunting task.…”

“…To this end, several calculations have been performed for super-heavy elements, most of them in the coupled-cluster approximation. Correlation energy for the ground state of elements with Z = 102 [67], 103 [68,69], 104 [70], 111 [71], 112 [72], 113 [73], 114 [74,75], 115 [76], 118 [77,78], 122 [79] have been calculated with this approach. The MCDF method was used for evaluating correlation on transition energies and rates for Fm and No, as well as for the element 118 [80,81,41] and 122 [82].…”

Relativistic electronic structure studies on the heaviest elements

“…The nuclear volume effect grows even faster with Z. Consequently, for the superheavy elements, its contribution to the orbital energy will be the second important one after the relativistic contribution. Thus, e.g., for element 118, QED effects on the binding energy of the 8s electron cause a 9% reduction (0.006 eV) of EA [25].…”

Heaviest Element Has Unusual Shell Structure

“…In contrast to its electronic configuration (Og completes the seventh period of the periodic table), it is not expected to behave like a typical rare gas of group 18. For example, the relativistic 7p 3=2 expansion and the relativistic 8s contraction make Og the first rare gas element with a positive electron affinity of 0.064 eV [10,16,22]. This result includes a substantial quantum electrodynamic correction of 0.006 eV [16].…”

“…This effect, particularly strong for neutrons, is due to the high density of single-particle orbitals. 118 Og, 0.89 þ1.07 −0.31 ms, is too short for chemical "oneatom-at-a-time" studies; hence, its chemical properties must be inferred from advanced atomic calculations based on relativistic quantum theory [6][7][8][9][10][11][12][13][14][15][16][17][18][19]. According to these, Og has a closed-shell ½Rn 5f 14 6d 10 7s 2 7p 6 configuration [13,20,21], with a very large spin-orbit splitting of the 7p shell (9.920 eV at the Dirac-Breit-Hartree-Fock and 10.125 eV at the Fock-space coupled-cluster level; see below).…”