Darmstadtium (110)

The Essentials

Darmstadtium [D-ARM-SHTAH-TEE-UM….as close as I can figure for pronunciation] is a chemical element with the symbol Ds and atomic number 110. It is an extremely radioactive synthetic element. The most stable known isotope, darmstadtium-281, has a half-life of approximately 11 seconds, but it is possible that this darmstadtium isotope may have an isomer with a longer half-life, 3.7 minutes (cannot confirm). Darmstadtium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt-Wixhausen part of Darmstadt, Germany. It was named after the city of Darmstadt, where it was discovered.

In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and is placed in the group 10 elements, although no chemical experiments have yet been carried out to confirm that it behaves as the heavier homologue to platinum in group 10. Darmstadtium is calculated to have similar properties to its lighter homologues, nickel, palladium, and platinum.

Chemically, darmstadtium is in the same Group as nickel, palladium, and platinum (Group 10). Unlike these lighter atoms, darmstadtium decays after a small fraction of a thousandth of a second into lighter elements by emitting α-particles which are the nuclei of helium atoms.

Name: Darmstadtium Symbol: Ds Atomic number: 110 Atomic weight: [ 281 ] Standard state: presumably a solid at 298 K CAS Registry ID: 54083-77-1

Group in periodic table: 10 Period in periodic table: 7 Block in periodic table: d-block Color: unknown, but probably metallic and silvery white or grey in appearance Classification: Metallic

Historical information

Darmstadtium was discovered by S. Hofmann, V. Ninov, F. P. Hessberger, P. Armbruster, H. Folger, G. Münzenberg, H. J. Schött, and others at 1994 in Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany. Origin of name: the name darmstadtium lies within the long established tradition of naming an element after the place of its discovery, Darmstadt, in Germany..

On the 9th of November 1994 at 4:39 pm the first atom of element 110, darmstadtium, was detected at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany. The isotope discovered has an atomic number of 269 (that is, 269 times heavier than hydrogen).

The new element was produced by fusing a nickel and a lead atom together. This was achieved by accelerating the nickel atoms to a high energy in the heavy ion accelerator UNILAC at GSI. Over a period of many days, many billion billion nickel atoms were fired at a lead target in order to produce and identify a single atom of darmstadtium.

Darmstadtium was the fourth element discovered at GSI. Between 1981 and 1984 the elements 107 (bohrium), 108 (hassium), 109 (meitnerium) were produced and identified there. Since the discovery of darmstadtium, elements 111 and 112 were both discovered at GSI.

As for the name, Darmstadtium (Ds) was suggested by the GSI team in honor of the city of Darmstadt, where the element was discovered. Before the discovery it was named Ununnilium (Uun). The GSI team originally also considered naming the element wixhausium, after the suburb of Darmstadt known as Wixhausen where the element was discovered, but eventually decided on darmstadtium. The new name was officially recommended by IUPAC on August 16, 2003.

Physical properties

• Density of solid: 27400 (predicted) kg m^-3
• Cubic centric crystal structure (predicted)

Orbital properties

• Ground state electron configuration:  [Rn].5f¹⁴.6d⁹.7s¹ (a guess based upon that of platinum)
• Shell structure:  2.8.18.32.32.17.1
• Term symbol:   ³D₃ (a guess based upon guessed electronic structure)

Isolation

Only a few atoms of darmstadtium have ever been made, initially through a nuclear reaction involving fusion of an isotope of lead, Pb, with one of nickel, Ni.

²⁰⁸Pb + ⁶²Ni → ²⁶⁹Ds + ¹n

Isolation of an observable quantity has never been achieved, and may well never be. This is because atoms of the element decompose through the emission of α-particles with a half-life of only about 270 microseconds. Another isotope was made by using a different isotope of nickel.

²⁰⁸Pb + ⁶⁴Ni → ²⁷¹Ds + ¹n