Lawrencium
Element 103 · Actinide
Lawrencium closes the actinide series. It was first produced in 1961 at Berkeley by bombarding californium with boron ions, yielding only a few atoms. Its longest-lived isotope has a half-life of about 11 hours. Experiments with single atoms show it behaves as a typical trivalent actinide, though relativistic effects give it an unusual 7p electron in its ground state. Properties are predicted, with limited experimental data. Lawrencium is radioactive, and its atoms decay within hours of being made.
Key facts
| Atomic number | 103 |
|---|---|
| Atomic weight | [266] |
| Category | Actinide |
| Group / Period | — / 7 |
| Block | f |
| Electron configuration | [Rn] 5f14 7s2 7p1 |
| Common oxidation states | +3 |
| State at STP | Solid |
| Melting point | 1627 °C (estimated) |
Occurrence
Lawrencium is entirely synthetic, produced atom-by-atom in accelerators. No macroscopic sample has ever existed.
Applications
Single-atom chemistry experiments
Tests of relativistic quantum-chemical predictions
No commercial applications
Common compounds
- Lawrencium(III) chloride (LrCl3, tracer scale)
- Lawrencium(III) oxide (Lr2O3, predicted)
Lawrencium is named after Ernest Lawrence, inventor of the cyclotron, the particle accelerator type used to create so many synthetic elements.
Data source: IUPAC standard atomic weights 2021