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arXiv · 2101.05809

Dramatic relativistic and magnetic Breit effects for the superheavy reaction Og + 3Ts$_2$ -> OgTs$_6$: Prediction of atomization energy and the existence of the superheavy octahedral Oganesson hexatennesside OgTs$_6$

Abstract

Our gargantuan ab initio all-electron fully relativistic Dirac-Fock (DF), nonrelativistic (NR) Hartree-Fock(HF) and Dirac-Fock-Breit-Gaunt(DFBG) molecular SCF calculations for the superheavy octahedral Oganesson hexatenniside OgTs$_6$ predict atomization energy (Ae) of 9.47, -5.54and 9.37 eV, at the optimized Os-Ts bond distances of 3.35, 3.34 and 3.36 angstroms, respectively. There are dramatic effects of relativity for the atomization energy of OgTs$_6$ (with seven superheavy elements and 820 electrons) of ~ 15.0 eV each at both the DF and DFBG levels of theory, respectively. Our calculated energy of reaction for the titled superheavy reaction Og + 3Ts$_2$ -> OgTs$_6$ at the DF, NR and DFBG levels of theory is 6.33, 8.81, and 6.26 eV, respectively. Mulliken analysis as implemented in the DIRAC code for our DF and NR calculations (using the dyall.ev4z basis) yields the charges Og(+0.60) and Og(+0.96), respectively on the central Og atom indicating that our relativistic DF calculations predict octahedral OgTs$_6$ to be less ionic. However, due caution must be used to interpret the results of Mulliken's population analysis, which is highly basis set dependent.

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Gulzari Malli, Martin Siegert, Luiz Guilherme M De Macedo, Walter Loveland. 2021-01-14. Dramatic relativistic and magnetic Breit effects for the superheavy reaction Og + 3Ts$_2$ -> OgTs$_6$: Prediction of atomization energy and the existence of the superheavy octahedral Oganesson hexatennesside OgTs$_6$. https://arxiv.org/abs/2101.05809

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