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
Atomic mass (282) g/mol
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
References

Darmstadtium ( IPA: /ˌdɑːmˈʃtatiəm/), 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 mass 279 and 281, have been subsequently synthesized and are more stable, with half-lives of 180 milliseconds and 11.1 seconds, respectively.

## 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:

${208 \atop 82}\mathrm{Pb}+{62 \atop 28}\mathrm{Ni}\quad\rightarrow\quad{269 \atop 110}\mathrm{Ds}+{1 \atop 0}\mathrm{n} \;$

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.

## Trivia

Some suggested (for fun) the name policium for the new element, because 110 is the emergency telephone number for the German police.