Rutherfordium
Element 104 · Transition Metal
Rutherfordium begins the transactinide series, where relativistic effects reshape chemistry. Predicted to behave like hafnium, its group 4 homolog, experiments with single atoms confirm it forms a volatile +4 chloride, matching expectations. Its longest-lived isotope has a half-life of about a minute. Because only a few atoms have ever existed at once, all properties are predicted, with limited experimental data. Rutherfordium is highly radioactive, with isotopes decaying in seconds to about a minute.
Key facts
| Atomic number | 104 |
|---|---|
| Atomic weight | [267] |
| Category | Transition Metal |
| Group / Period | 4 / 7 |
| Block | d |
| Electron configuration | [Rn] 5f14 6d2 7s2 |
| Common oxidation states | +4 (predicted) |
| State at STP | Solid |
Occurrence
Rutherfordium is entirely synthetic, produced by fusing lighter nuclei such as plutonium-242 with neon-22 in particle accelerators.
Applications
Single-atom gas-phase chemistry experiments
Benchmarking relativistic quantum-chemical models
No commercial applications
Common compounds
- Rutherfordium tetrachloride (RfCl4, predicted)
- Rutherfordium dioxide (RfO2, predicted)
Rutherfordium's discovery was disputed between Dubna (1964) and Berkeley (1969); it honors Ernest Rutherford, father of nuclear physics.
Data source: IUPAC standard atomic weights 2021