Bohrium
transition metalProperties
| Property | Value |
|---|---|
| Atomic Mass | 270 amu |
| Category | transition metal |
| Group | 7 |
| Period | 7 |
| Electron Configuration | [Rn] 5f14 6d5 7s2 |
| Oxidation States | 7, 5, 4, 3 |
| Discovered By | Peter Armbruster, Gottfried Munzenberg, GSI Helmholtzzentrum (1981) |
About Bohrium
Bohrium is a group-7 superheavy that exists, when it exists, for tens of seconds at a time. Peter Armbruster and Gottfried Münzenberg's team at GSI Darmstadt made the first six atoms in 1981 by firing chromium-54 ions at a bismuth-209 target in the SHIP velocity filter — atom-by-atom chemistry, with the entire experimental record fitting in a notebook. The most stable isotope, Bh-270, has a half-life around 61 seconds, which is just enough time for gas-phase chromatography. In 2000 a Berkeley/PSI/JINR collaboration confirmed that bohrium forms a volatile oxychloride, BhO₃Cl, with adsorption behavior that places it cleanly below rhenium and technetium in group 7 — relativistic effects on the 6d electrons did not reshuffle the chemistry the way they do for some neighbors. That single result was a triumph of stopwatch-grade analytical chemistry: detect the daughter alpha decay before the parent atom is gone.
Fun Fact
Bohrium was the first element discovered at GSI Darmstadt — a facility that would go on to add five more (hassium, meitnerium, darmstadtium, roentgenium, copernicium) to the periodic table.
Common Uses
- Single-atom gas-phase chromatography of group-7 oxychlorides
- Tests of relativistic effects on 6d-electron chemistry
- Probes of nuclear shell structure near the predicted island of stability
- Calibration of cross-section predictions for cold-fusion reactions
- No commercial applications