Darmstadtium
Transition metal (predicted) · Period 7 · Group 10 · d-block
Made in Darmstadt, named for Darmstadt
- Atomic mass
- 281 u
- State at 25 °C
- Solid
- Electronegativity
- —
- Melting point
- —
- Boiling point
- —
- Configuration
- *[Rn] 5f14 6d9 7s1
Nucleus drawn at reduced count for clarity. Drag to rotate.
Darmstadtium, explained
Video lesson in production
Bhavya’s explainer for this element will play here.
Overview
Darmstadtium is a group 10 element, the heavy cousin of nickel, palladium and platinum. Calculations predict a 7s2 6d8 configuration, unlike platinum's 6s1 5d9, because relativistic stabilization of the 7s orbital favors keeping both s electrons. It is predicted to be a dense noble metal with oxidation states up to +6, but no chemical experiment has been performed: its isotopes are too short-lived and too rarely produced.
The darmstadtium isotopes first made in 1994 lived for fractions of a millisecond. Later, darmstadtium-281 was found in the decay chains of flerovium made at Dubna, with a half-life of roughly 13 seconds, many thousands of times longer. That jump reflects the extra neutrons in 281Ds, which bring it closer to the predicted island of stability, a region where closed nuclear shells should make superheavy nuclei longer-lived.
Discovery
Sigurd Hofmann's team at GSI in Darmstadt made darmstadtium on 9 November 1994 by bombarding lead-208 with nickel-62, detecting one atom of darmstadtium-269; weeks later they made darmstadtium-271 using nickel-64. Earlier claims from Dubna and Berkeley had not been confirmed. IUPAC credited GSI in 2001, and the name darmstadtium, after the city where GSI is located, was approved in 2003.
- Where it’s found
- Darmstadtium does not occur in nature; it is made in accelerators or appears in the decay chains of heavier elements.
- What it’s used for
- Nuclear structure research
- Island of stability studies
- Decay-chain identification
- Cold-fusion research
- In living things
- Darmstadtium has no biological role; it is radioactive and exists only as individual atoms.
- Safety
- Radioactive and made only a few atoms ever; it decays within seconds or less.
How it compares
Where Darmstadtium sits among all 118 elements on the trends that shape the table.
- ElectronegativityNo data
Not measured for this element
- Ionization energyNo data
Not measured for this element
- Atomic radiusNo data
Not measured for this element
- Electron affinityNo data
Not measured for this element
- Density34.8g/cm³
#5 of 114 elements with data · predicted
- Melting pointNo data
Not measured for this element
- Density
- 34.8 g/cm³
- Atomic radius
- —
- Covalent radius
- —
- Molar heat
- —
- Appearance
- —
- Discovered by
- Gesellschaft für Schwerionenforschung
Inside the atom
110 electrons arranged in 7 shells: 2 · 8 · 18 · 32 · 32 · 16 · 2.
Orbital diagram
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d8 · shorthand *[Rn] 5f14 6d9 7s1
- 1s2
- 2s2
- 2p6
- 3s2
- 3p6
- 4s2
- 3d10
- 4p6
- 5s2
- 4d10
- 5p6
- 6s2
- 4f14
- 5d10
- 6p6
- 7s2
- 5f14
- 6d8
Each box is an orbital holding up to two electrons of opposite spin. Highlighted subshells hold the valence electrons that decide how Darmstadtium bonds.
Signature reactions
How the first atoms were made, and how they fall apart.
Nuclear · Cold fusion
GSI cold-fusion synthesis
Nickel-62 fuses with lead-208 and the compound nucleus emits one neutron. Production rates were so low that days of bombardment were needed for each atom.
Conditions: nickel-62 beam on lead-208, GSI UNILAC, 1994
Nuclear · Alpha decay
Alpha decay of darmstadtium-269
Darmstadtium-269 emits an alpha particle to become hassium-265, the isotope GSI had first made in 1984. The match to a known daughter confirmed element 110.
Conditions: spontaneous, half-life about 0.2 milliseconds
Where you’ll meet it
Darmstadt Artists' Colony
The Mathildenhöhe art nouveau colony is among the best-known sights of darmstadtium's namesake city.
Photo: Wikimedia Commons
Platinum
Platinum, directly above darmstadtium in group 10, is the model for its predicted noble-metal chemistry.
Photo: Wikimedia Commons
Island of stability
Longer-lived isotopes such as darmstadtium-281 sit closer to this predicted region of enhanced nuclear stability.
Photo: Wikimedia Commons
Research
No research on Darmstadtium yet
When Bhavya publishes a project that studies Darmstadtium, it will be linked here.