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The chemical separation of Eka-Hg from CERN W targets in view of recent relativistic calculations

  • D. Kolb , A. Marinov , G. W. A. Newton and R. Brandt
Published/Copyright: May 5, 2013
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Abstract

In 1971 evidence for the production of element 112 via secondary reactions in CERN W targets was obtained. The evidence was mainly based on the observation of fission fragments in Hg sources separated from the W targets, on the measured masses of the fissioning nuclei and on the assumption that element 112 (Eka-Hg) actually behaves like Hg in the chemical separation process. This assumption is analyzed in view of recent relativistic calculations of the electronic structure of element 112. It is shown that in the superheavy element region only the chemistry of element 112 is similar to that of Hg.

Kurzfassung

1971 erhielt man experimentelle Evidenz für die Erzeugung des Elements 112 aus Sekundärreaktionen in W Targets am CERN. Die Evidenz basierte hauptsächlich auf der Beobachtung von Spaltfragmenten in Hg Fraktionen, die aus den W Targets chemisch abgetrennt worden waren, den gemessenen Massen der spaltenden Kerne und auf der Annahme, dass Element 112 (Eka-Hg) sich in dem chemischen Trennprozess ähnlich wie Hg verhält. Diese Annahme wurde unter Berücksichtigung neuer relativistischer Berechnungen zur elektronischen Struktur des Elements 112 analysiert. Es wird gezeigt, dass in dem Bereich superschwerer Elemente nur die Chemie des Elementes 112 ähnlich der von Hg ist.

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Received: 2004-11-12
Published Online: 2013-05-05
Published in Print: 2005-05-01

© 2005, Carl Hanser Verlag, München

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