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Superheavy elements a prediction of their chemical and physical properties

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... For the heaviest elements, however, the highest core level (n−1)p 4 3/2 moves up into an energy range typical for strongly electronegative elements, and becomes radially less compact (Figures 7, 8). Fricke and Waber (Fricke and Waber, 1971;Fricke, 1975) had already speculated about raised valences of elements 119 Uue and 120 Ubn. In more recent years, computations and experiments up to the megabar range have established the stability of alkali and alkaline-earth polyhalides under high pressure met inside the planets (Dong et al., 2015(Dong et al., , 2017Zhu et al., 2015;Goesten et al., 2017;Miao et al., 2017;Luo et al., 2018;Lin et al., 2019;Rahm et al., 2019). ...
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