Meitnerium
Element 109 · Transition Metal
Meitnerium is the group 9 transactinide, expected to resemble iridium. It was first made in 1982 at GSI Darmstadt, with a single atom detected in the discovery experiment. Its isotopes decay within milliseconds. No chemical experiments have yet been possible, so all properties are predicted, with essentially no experimental data. Meitnerium is extremely radioactive, decaying within milliseconds.
Key facts
| Atomic number | 109 |
|---|---|
| Atomic weight | [278] |
| Category | Transition Metal |
| Group / Period | 9 / 7 |
| Block | d |
| Electron configuration | [Rn] 5f14 6d7 7s2 (predicted) |
| Common oxidation states | +3 (predicted) |
| State at STP | Solid |
Occurrence
Meitnerium is entirely synthetic, produced one atom at a time by fusing bismuth-209 with iron-58.
Applications
Nuclear physics research on superheavy stability
Future single-atom chemistry (not yet achieved)
No commercial applications
Common compounds
- Meitnerium compounds (predicted, none observed)
Meitnerium honors Lise Meitner, whose explanation of nuclear fission was overlooked for the Nobel Prize awarded to her collaborator.
Data source: IUPAC standard atomic weights 2021