Darmstadtium

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110 meitnerium ← darmstadtium → roentgenium
Pt
↑
Ds
↓
(Uhn)
Periodic Table - Extended Periodic Table
General
Name, Symbol, Number darmstadtium, Ds, 110
Chemical series transition metals
Group, Period, Block 10, 7, d
Appearance unknown, probably silvery
white or metallic gray
Standard atomic weight (282)  g·mol−1
Electron configuration perhaps [Rn] 5f14 6d9 7s1
(in analogy to platinum)
Electrons per shell 2, 8, 18, 32, 32, 17, 1
Phase presumably a solid
CAS registry number 54083-77-1
Selected isotopes
Main article: Isotopes of darmstadtium
iso NA half-life DM DE (MeV) DP
281Ds syn 11 s
References

Darmstadtium (IPA: /ˌdɑ(ɹ)mˈʃtatiəm/), formerly called ununnilium (IPA: /ˌjuːnuːˈnɪliəm/, symbol Uun) or eka-platinum, is a chemical element with the symbol Ds and atomic number 110. It is one of the so-called super-heavy atoms. This synthetic element quickly decays: its isotopes of mass 267 to 273 have half-lives measured in microseconds. Heavier isotopes of darmstadtium, of mass 279 and 281, have been subsequently synthesized and are more stable, with half-lives of 180 milliseconds and 11.1 seconds, respectively.

Contents

  • 1 History
  • 2 See also
  • 3 References
  • 4 External links

[edit] History

Ds was first generated on November 9, 1994 at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany by a team headed by Dr. Jorge Rigol. Only a few atoms of it were prepared by nuclear fusion, involving bombarding a lead target with nickel:[1]

\,^{208}_{82}\mathrm{Pb} + \,^{62}_{28}\mathrm{Ni} \, \to \,^{269}_{110}\mathrm{Ds} + \; ^1_0\mathrm{n} \;

The element was named after the place of its discovery, Darmstadt (the GSI is located in Wixhausen, a northern portion of the city). The new name was given to it by the IUPAC on August 16, 2003.